Well got my gauges back for a trial fit with mixed results.
I swapped out 4 gauges, oiled the clock and replaced the tach cable.
When I brought this car home in February the tach wasn’t working at all, then little by little decided to work but bounced around.
The oil pressure gauge wasn’t working because it leaked at the gauge and the owner just disconnected it at the block.
The amp gauge was stuck in discharge likely damaged by the leaking oil and or an overheated horn relay which cooked the fusable link running from the horn relay to the amp gauge.
I cleaned up the fuse block and found the gauge fuse was blown. I replaced it and the fuel and temp gauges appeared to work.
Ok it’s back in enough to test the work done. The clock works as does the oil pressure gauge without leaking. Great.
On the down side the amp gauge is doing nothing and both needles in the fuel and temp gauges have succumbed to gravity and are pointing down and the gauge fuse has blown again.
Now I’m studying my wiring schematic trying to plan my next course of action.
Assuming I have a wire on the gauge circuit shorting out so I’ll check continuity on that circuit to ground.
As for the Tach, it’s dead with the new cable so it’s probably needing a new worm gear.
Right now it’d be nice to get the temp and fuel gauge sorted out.

 

Lt. Sorry, I don’t remember the model year of your car. Wilcox has a step by step guide to check the “Battery Gauge” before you run
out and buy a new one. I bought a AGM Battery and now my battery gauge is bouncing all over the place. I checked the wires going to the horn relay and they are tight. At the car show yesterday. one of the guys told me to check the ground wire from the battery. Aren’t these cars FUN!

 

Ya they are Sorry I’ve been trying to remember to put (‘68 L68) at the top but my head was clouded last night.
I considered the AGM battery but heard about issues with a trickle charger, that a normal battery tender won’t work. You need to get one specifically for the agm battery. Also possible issues with jump starting if needed. Decided not to overcomplicate things and stayed with a normal battery.
Went to bed and woke up thinking about the gauge issue.
Got a plan now and ran out today to pick up an in-line fuse holder.
I studied my wiring schematic and found 4 things on that circuit, fuel, temp, door ajar lamp and parking brake lamp. It’s safe to say something in that circuit is grounding out but though there’s only 4 possibilities it’ll still be a pain to find and repair the short.
I saw the video posted by Wilcox on testing the gauge and it all points to a power lead problem.
In the video he shows if there’s no power to the gauge the needle could point anywhere but given power it’ll return to position.
Not to do a Bubba repair but I’m going to bypass the line exiting the fuse block and run my own fused lead to the fuel and temp gauges.
not worried about the warning lamps right now.
Getting it working in this way is as much a diagnostic measure to confirm a wiring issue. No reason I can’t run it that way for awhile. In the off season I can order a new wiring harness to make it right.
Wish me luck

 

Got the fuel and temp gauge working which I’ll be honest and say it was my mistake, the gauge came with its own card and nuts which have to be removed when installed otherwise it grounds out. Being tired and flustered doesn’t help . A fresh perspective and a clear head are definitely a plus.
The amp gauge is still not working but I verified power on the terminal (black w/white stripe) leading back to the horn relay but nothing on the lead that ties in with the line to the starter solenoid.
more than likely that’s a fried fuseable link wire again.
Ps - The by pass did help
me diagnose the issue but in the end I did use the factory harness

 

Got everything back together and when hooking up the cigarette lighter I bumped the positive lead to ground.
Gotta say this was not fun getting everything to fit right. I’m definitely not the first in this dash as there’s a lot of repo panels and I’ve had figure out not only how the factory had it but what the prior owner(s) did. Got it all together and I notice the clocks not running .
I check the gauge fuse and it’s fine. About that point my wife says dinners ready. After dinner I was tempted to settle in but kept thinking about having to pull the dash apart again and knew I’d lose sleep if I didn’t sort it out now.
Back out and found though the clock is in the gauge cluster it’s fused with the cigar lighter. New fuse made it right.
All the other little issues I found today wore me thin but I’m closing in on it.
Like to say it’s been fun but I’d be lying.
What I wanted to buy was a completely ready to drive problem free car but I’m thinking for me that doesn’t exist. Everything has to work and I’m thinking most folks are willing to settle for less and consider that a restored car.
Can’t get my head around that.