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I am in process of building my '50 3600 with a 383 SBC engine that I anticipate installing all new wiring in. Some of the wiring will be standard '50 such as lights and heater blower, but I also have an electric fan, electric fuel pump, eelctric wipers, newer style alternator, HEI ignition, etc. I will not have power windows, power door locks, power seats, or radio.

Painless Wiring seems to be the "best" source for a new custom type harness (21 circuit) but they are pretty pricy. Speedway has a universal version (22 circuit) that is similar to the Painless for about $100 less. However, ther are several listings on E-Bay that appear to be similar 21 or 22 circuit versions that are roughly $100 less than the Speedway option.

I don't want to be cheep but I also don't want to be paying for different sources that are providing basically the same product.

Anyone having experience with a source for a cutom wiring harness to help me decide which approach to take would be appreciated.

Why not just purchase a fuse panel from Painless or whomever and wire each circuit individually yourself?

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I probably could but I think there is some value is buying a harness that has all (or at least most) of the different colored wires etc. that are typical GM color coded and have the circuite identification on the wire. I realize that this is no way going to be plug and play but buying 21 or 22 different wire colors to make my own harness does not seem like a gret option.

I have used the painless, the speedway, and the generics, as well as building a couple from scratch.

For one vehicle, it is about break even to buy spools of wire and build it yourself. It is more work, but you know exactly how everything is wired and that it is done right. If you are going to do a second vehicle, the material cost is paid for at that point. This solution is not for everyone.

The Painless and Speedway harnesses are pretty equivalent. You pay more for the Painless name, but it really isn't a better product.

The cheap generic harnesses are generally fine, but the quality control is much looser. Sometimes the wrong color is used, or a circuit that should be ignition switched isn't, or a crimp is a bit loose and needs fixed. If you are on a budget and don't mind going through a new part, inspecting it, and making sure it is good to go, these are serviceable.

I specifically got one of the cheap ones for my daughter's jeep so that we could go through it together as a learning/troubleshooting exercise.

Fibonachu, thank you for the information, exactly the kind of input I was hoping for.

I hope your daughter appreciated the opportunity as it would be great for anyone trying to learn about electrical systems and related trouble shooting.

I've done lots of wiring.
My advice.
1. Do not try to build your own. You must use a prewired fuse panel, universal style harness.
2. Do not buy from an Ebay seller unless it's one of the trusted vendors. They also sell on Ebay.
3. The Speedway universal 12 or 22 will work fine.

I don't know your experience with wiring. The harnesses require crimping. A good tool helps a lot. Most harnesses support alternator and HEI. 12 circuits should be enough. Soldering of terminals is not necessary. You asked for "custom". Not necessary. "Universal" is what you want and seem to be looking at. Two different words with totally different prices.

The price difference of universal harnesses is sometimes justified depending on the "extras". I.E. Switches, extra connectors, lamp sockets, fuse panel style and so forth. So factor that in if you need those......but all that is available separately as you see the need later.

My Tips and futher suggestions:
1. The fuse panel is best mounted upper left of your left foot, inside cab.
2. Abandon the "terminal blocks" that were mounted on the inner fenders. Direct wire, using a soldered splice where necessary to crossover.. Use same splice for rear tail lights crossover/license light.
3. The wire bundles that go thru the firewall are routed down the left innner fender to front and down the left frame rail to rear.
4. Wire colors and quality are all the same for all the vendor's harnesses.
5. Crimping with heat shrink sleeving covering the "joint" is best.
6. Watch some vids on crimping provided by vendors: AAW, painless, speedway, EZ, etc
7. Use the braid type ground straps to get the motor, frame and body bonded to battery neg.
8. None of this is real hard to do.
9. It's your truck, you can do anything you want, any way you want, using any harness or technique you want.

Vendors= all the known companies we use that specialize in old, classic, vintage trucks.

Curious, why not build your own?

Hi Mark, how are you? This is my opinion answer.

'Why build your own? It's more work, Have to buy wire, can't get all the colors easily. Have to buy connector shells, have to buy contacts for the connector shells, have to buy terminals, have to buy, and wire, a fuse panel. Have to buy boots, switches, flasher, fuses.....Wires have no markings every 6 inches. Terminals, packard 56 shells and contacts have min quantities at some vendors. No returns, no instructions, no free shipping and same price or more. No advantage whatsoever.

Been there, done both. Buying one is the way to go.

Alternate opinion: There are plenty of reasons to build it yourself.

If you are doing a single vehicle, the cost to buy the supplies is comparable to a Painless or Speedway harness. If you do much electrical work, the extra wire you will have left over is good for all kinds of things. If you plan to wire more than one vehicle, the savings are fairly substantial over the high quality off-the-shelf setups.

Building your own harness lets you route things exactly how you want them, combine or separate fuses as desired, select from a wide variety of shapes and styles of fuse blocks to fit your physical location and/or cosmetic desires. You can also select a fuse block that uses the style of fuses you prefer (whatever that is). You can select your own wire sizes on a per-circuit basis to match the intended use as well.

As far as instructions go, that is what a wiring diagram is for. These trucks are pretty darn simple.

Putting the ends on the wires takes a few seconds each. The greatest majority of fuse blocks you can buy have pins that your crimp on and slip into the fuse block, so no additional tools are needed over what you already need for the other ends of the wires.

That said, I do agree with a number of the points made above.

Making your own harness from scratch does take more time and effort.

You do have to read the wiring diagram and hook things up properly, but if you are not capable of that, you probably should not be doing any wiring changes.

Having wires labelled along the length is fine. Painless started that and pushed it as a big deal. I have never been particularly enamoured with it because it locks you even further into hooking everything up exactly the way they intended. Some people really like it as a feature, your mileage may vary.

If you are not planning to do anything different than the last 2500 people who rewired a truck, any of the solutions will probably work fine for you. You trade effort for cost up to a point. Based on your intial post, this sounds like a pretty simple wiring job.

The smaller harnesses (12-14 circuit) will probably meet your needs and be cheaper than a 21+.

Thank you all for your thoughts and input.

I decided to go the middle of the road approach and ordered the 22 circuit kit from Speedway. In part because it was less cost than Painless and in part because I liked the idea of having extra capacity (over the 12 circuit version) in case I change my mind later about some of the things I currently do not plan to have.

I am sure that doing my own would have worked out just fine and I still may regret not taking that approach but I do not anticipate doing more than one vehicle so the sourcing of all the different wire colors, terminals, etc. seemed like a bigger hassle than I wanted to take on.

I do anticipate mounting the fuse panel on the interior driver's side cowl panel and routing the wire bundles as described above to the front and rear. Braded ground straps are also planned. My battery will be in the standard location (below floor on the right side) making it easy to route positive battery connection to the starter and main ground strap from the battery to the engine block. Given the effort to clean, prime, and paint everything I may run ground wires rather than relying on using the body or frame for ground connections.

I'm a little late to the party here but I agree picking up a premade one is the quickest route by far. The last one I installed even had all the circuits labelled on the wires(!!) and the taillight wires were long enough I could have put tail lights on a 747 if I'd cared to.

I put the fuse panel on my 49 up under the driver's side cowl like you're thinking, works and its out of the way. No worse than any other vehicle out there.

Good luck! I enjoy wiring.

Hey bartamos, doing fine. You?

Maybe I'm a little off my rocker. I enjoy making my own harnesses. The crazy part is, I use as many Deutsche connectors as I can. Not sure why I enjoy it so much. I actually find it very calming.

I'm with Mark. I've been rebuilding my original harness, adding turn signal circuits and repairing deteriorated wires. It makes a good inside project. When I'm working on it my wife wonders where I am.

But I have to agree with bartamos about DIY harnesses not being the easiest (or least expensive) route. DIY wiring isn't for everyone.

Same here - making my own harnesses is quite meditative and therapeutic for me. Especially when I can start with a blank slate.
I discovered those twisted "MilSpac" or "Aviation Style" way of doing harnesses for race cars a while ago, and got totally into that.
Though it is an total overkill for our sort of vehicles, it's a lot of fun and really satisfying.

I don't use any modern connectors though - that would be bad for my harness Feng Shui ;-)

best, Frank

I did not know about the members who need to build a harness for the soothing effect. Just sticking with practical advice.

I'm with Bartamos on just buying a full harness (or the section you need - if that is available)... I am about $350 deep (not counting labor) into a $100 self built harness.

Just don’t add in the cost of tools and “incidentals” and you can still pretend you’re breaking even building your own.

That’s what I’m doing.

I'm probably in the same situation as Rusty Rod on my harness stuff. But I don't want to add up the cost. I'm a cheapskate so just buy a little at a time so it doesn't cost as much. (Actually, I just don't remember to get everything I need at the same time, so multiple orders. )
Pretend I'm breaking even -- Yeah, That's the ticket.

looks like building your own can be anti-soothing. Anyway looks like cruiser has done the practical thing.

WICruiser, you will probably need help in a few areas. Email me if you want to.

Thanks again to all those that have responded and thank you bartamos for the offer. I know that getting the harness is only the beginning and my truck has a long way to go (as you may have noticed from my Project Journal) so it is likely to be a while before I get far enough to actually determine that I need help.

I have plenty of time and I also will wire my own. While not an electrician, I do want to route things 'my' way so it looks professional. I notice plenty of different gauges of wire (besides colors) - what's the thinking of using 12 ga throughout and either band the ends in a colored tape or heatshrink ? Call me crazy, but I just rebuilt stupid Fiat motor last year, so anything else is cake. ( just pulled up Amazon - 500' 12ga = $85 )

There are a few reasons you may reconsider you choice of wire gauge:

1) Some of the wires are 10 gauge.

2) Cost. The cost is 12 gauge is much more than 14 or 16 gauge. At Autozone:
12 gauge primary wire, 100 ft = $44.99
14 gauge primary wire, 100 ft = $22.99
16 gauge primary wire, 100 ft = $18.99
In addition, your connectors are quite a bit more for 12 gauge.

3) 12 gauge connectors may not fit on some of the terminals and your wire loom will end up being really big especially coming thru the firewall. You may not fit that many 12 gauge wires thru the existing hole.

Look at the existing wiring diagrams for gauges, then alter it to fit your needs and preference's.

I checked shop manual - which ones are 10ga ?

I used 10 ga primary wire just for the Alt and HEI power.

Ditto the above on using 12GA for everything.

The biggest downside to using the same color for everything is tracing wires. If you end up with harness damage down the road, telling what wire is what becomes a nightmare. Even just troubleshooting issues is much worse.

If you want to limit how many things you buy, I would go to Waytek wire and get at least 4 colors. That lets you use different colors for things going to the same area and it will make things easier.

If you have multiple colors, you can pull them all at the same time if they are going to the same place (such as taillights).

Just an FYI, because the tail light/stop light wires to the rear were short I used a trailer wiring harness that had not only the different color wires but printing on the wires to extend them. As I am no where near ready for rear lights I have the extension connected to the harness wires but the whole extension "stored" in the rar frame area until I get to the point of knowing exactly what I need.

Well, I hoping to not have ... " harness damage down the road ".
And I'm getting a 10-pack or colored tape just for the ends that matter.
Should clarify - most of cluster working ok. The frame and engine bay
ones will be main concern. And that isn't very many.

my takeaway; what raises blood pressure for some...is "soothing" for others! lol