I had a whole thread on the volt meter install but lost it so here's the abridged version.
Found one of these at Carlisle for a couple bucks.
Comparison to the stock ammeter.
Popped the bezel off with a small screwdriver to take the gauge apart. Ammeter behind it for comparison.
Yep, gonna work but the gauge face doesn't look right or fit
Back side shows that I'll need to open up the mounting holes and use the fiber washers for electrical isolation.
Used a file to fit the stock back plate to the Sunpro gauge
Fiber washers installed. I think I opened the holes with a unibit.
Some decals I made up at work while trying to get a decent font match.
Done.
For the wiring I just rewired the main cluster connector for +vdc and ground.