The Stovebolt Site Forums The Shop Area Interiors Removing Gauge Assemblies in a 1951 GMC 100

Looking for links to DIY resources, videos for speedometer and combination gauge assemblies removal. It seems like the assemblies should come out easily, I just couldn’t find the clip to push or screw to remove the assemblies, any tips, especially with pictures or diagrams to help me remove the assemblies is appreciated.

Preparing for a new wiring harness install, both gauge assemblies need to be refurbished. I would like to keep original assemblies and install 12 V upgraded fuel, temp etc gauges.


Thanks!

The gauge assembly and speedometer are held in by studs welded to the back of the dash and 3/8 (IIRC) hex nuts accessed from the back. Use a nut driver and the braille method to get on the nuts. There are 4 per assembly. Once you have the nuts out, the assemblies go out thru the back.
Here's a couple pics of the gauge assembly showing the ears where the studs go thru. This is off a Chevy, but your GMC will be the same.

Stand at the door, lean your shoulder in at the light switch, and go through the motion like your curling your bicep. Like Kevin says, have that nut driver in your hand. The ones down near the column will give you the hardest time. Mostly because of all the wires, collected mud, etc.

Do you have a picture or a link to where I can purchase the correct length of nut driver?

They are all about the same. A 1/4" ratchet set works real nice, too.

If you're concerned about the length of the stud, a 1/4" deep socket works nicely. I have a screwdriver style handle for 1/4" sockets that gets used a lot.

FWIW when you go to REinstall: I turned some long knurled nuts for mine (it was a tip I read here on a Stovebolt post). Eliminates the need for extra tools under the dash, they don't have to be particularly tight, just snug. You could have wingnuts on there if you wanted more leverage, but they will have to be extended for the wings to clear the housing. Believe the thread is #10-24. You could fabricate them other ways if you don't have access to a lathe.

I just had the gauges out again yesterday for some maintenance - so much nicer just to reach up and do it by hand.

One thing about these old girls is that if something isn’t coming off, it is either bolted down or screwed on. There aren’t many “clips” on them and if you find them, they’re usually made of spring steel and not plastic.


Ahhh...

Thanks Mark, Kevin, Northcoast3800, and Fox for your invaluable input. Yesterday, after a setback removing rusted on mirror bracket screws, I switched to removing my gauges.
After doing the bicep curl method, I successfully removed them both. Luckily, about half of the nuts come off by hand, and I used a small crescent wrench, and a 3/8 socket to remove the others! I really needed that win! I can’t thank you enough..

I do like the suggestion one of you made of replacing the stock nut with an easier to remove by hand substitute, as I can see future gauge upgrades once I replace my gas tank, Install my wiring harness, and add a missing linkage on the QuadraJet.

I plan on refurbishing both assemblies back to original look, as well as to work with the swapped in 350V8. Any suggestions on suppliers for gauge restoration, especially 12 V compatible?

Thanks again, I appreciate you brothers!

Huge win!

I have used Classic Parts for a replacement 12v gas gauge with success. Here is a link. https://www.classicparts.com/1947-51-Fuel-Gauge-GMC-w_-Red-Needle-12-Volt/productinfo/24%2D700BG/