Aftermarket gauges in stock cluster

This is going to be a long post, so I will break it up a little bit. This past summer I finally got around to fixing my instrument cluster on my 83 K20 because the only one that kind of worked was the fuel gauge that read 1/4 tank at full. My dad owned the truck before me and had mounted a temp and oil pressure gauge on the dash, but the oil pressure line had a pin hole and was getting oil all over the cubby.


I had a spare cluster, so I started out with the simple solution of trying to just install that one. But the only gauge that worked was the fuel gauge. The speedometer cable connector was different on that one, so I was out of luck using that one even though it was in better shape. Digging into it more a realized the reason none of my gauges worked was because all the stock sensors were never replaced when the engine was replaced 100k miles ago.

I test fit the old aftermarket gauges in my spare cluster, and it seemed like I would be able to make cheap aftermarket gauges work without breaking the bank.


I put the cover over and it mostly looked OK.

Since the fuel gauge worked on the spare cluster, I took that out and put it in my original cluster right away so could at least know how much fuel I had.

Here are the backs of the two speedometer gauges I have.

After spending days/weeks reading forums on getting my speedometer to work and failing. I decided to order a glowshift gps speedometer.

I got Equus oil pressure, temp, and voltage meters, and decided to get a glowshift tach to fit in the spare spot in the cluster. Figured it would be nice to have a tach since it is a manual.

Using these gauges in the stock cluster was light on the wallet, but heavy on the time investment. I wanted to give up a few times with how frustrating it was Using my dremmel tool to cut out the old thick plastic on the cluster back.

Wiring was something that I spent a good amount of time looking into before I started this project. Ended up buying the shop manuals from 83 on Rockauto and sketched up my own wiring schematic to try to make it easier to understand.

I decided that I wanted to keep as much of the original wiring as I could to make sure the blinker and other indicator lights remained working. I ended up drilling some holes in the back of the cluster and put bolts through to jumper wires for ignition, headlights, constant, and ground.

I cut the clear plastic lens to protect the needle on the fuel gauge. Broke more than one needle on those old gauges.

Overall happy with how it turned out. Though, I would probably not do it a second time. Also would have gotten a different speedometer, because the one I bought only has a trip meter and not an odometer...


The gps speedometer is a little slow to react. About 2-3 seconds of delay before it catches up. I checked the accuracy against my phone's speedometer app, and they read the same and have the same delay.

If you have any questions let me know. I started this project in July and didn't get it finished until Oct. It was my daily driver during this time, so couldn't completely take it out of commission and only worked on it a little at a time.