The original, expensive type are not the way to go. Most are the same pvc wire as used in the universl kits, with cloth covering, no fuses, no expansion possibilities. Rip Off.
DIY does not save any money and collecting all the parts is a real hassle. many times you have to buy minimum orders with electrical supply companies. Depending on the era of truck. The kits have good packard 56 connectors. Semi era correct and necessary in some cases. Time to get rid of the inner fender terminal blocks also.
The way to go especially with a 12v conversion is a universal prewired fuse panel kit. Advise alternator at that time also. These harnesses are pretty easy to install. Many of us can help. I have much experience with them. Easy to install. Our old trucks are very simple. Very few wires.
Speedway has a 12 Circuit for $186. A 22 circuit for $203 (may be the best value). Amazon as low as $125. Jeggs, Summit, Classic Trucks, Painless, EZ Wire, AAW, etc. Don't but from a funky place/guy.
These kits will need you to crimp. Good crimpers are available. Solder is not necessary with a good tool. These kit sellers all use basically the same quality automotive wire. The prices reflect number of circuits and the extras provided in kit. Just check out the literature for the one you wish to buy.
Most say do not support ammeter, some say don't support generators.
Probably repeated some of what Fibonachu said.
So now we have two engineers helping an engineer. Should get all screwed up in no time.
Using this thread because it seems pretty germane to the original question.
One last moment of doubt before I hit “buy it now” on some wire and other supplies and there’s no turning back on my Johnny Cash Rewire project.
I have never been under the illusion that my completely DIY approach would save time or money. And I am still completely OK with that. It was more about the hassle of modifying a cookie cutter harness to accommodate the way I want this done. It was also out of resistance to taking the truck off the road for a few weeks when I had just gotten the truck on the road. Those factors are still in play.
However, I’ve now done enough reading, YouTubing, planning, etc…. that my understanding of 12v automotive electrical is at a completely different place than it was a few months ago. I am much more comfortable with the idea of modifying an existing harness to do things my way. Up to and including de-pinning and re-pinning a universal if I had to.
Anywho…
It occurred to me last night that the “where and how to mount” custom panel is probably the biggest remaining undecided. Having it out of sight, relatively easy to service…those goals are competing with the amount of space my custom approach will require. And boy, those universal 12-circuit kits sure are compact.
That’s a whole bunch of backstory to arrive at this question:
What is the lowest prices 12 circuit harness with a decent and verifiable wire spec?
I cannot find a universal that has a verifiably decent wire spec (GXL) for less than the Speedway 12 circuit @ $185. That would be the very most I’d care to spend, given the amount of modification I’m likely to do. I don’t want to go cheap and get a kit with wire of VERY questionable origin and quality.
I haven’t accumulated a LOT of stuff just yet, but enough that the cost of a decent universal would likely exceed what I’ve budgeted and priced to do it from scratch.
