for the gage illumination I can take the oil pressure socket when lit up and move it to the volt gage and the bulb turns off then i put it back to oil pressure gage and it lights up.
I will move the ground for the voltmeter from the dash to somewhere else and see how that does.
this light socket thing just has me scratching my head. could be an issue with the ground of the gage, I have no idea but stranger things have happened.
thanks for the tips
IMGTX is correct on the fluctuation.
On the light a couple of ?
1. Is the Volt gauge housing metal or plastic?
2. Is the light socket 1 or 2 wires
3. have you tried the V gauge light in the OP gauge?
you could have
1. a flakey 12V connection to the socket
2. A flakey ground connection
3. Flakey connection between the socket contacts and bulb.
try moving the wire( with the bulb in place.
You are on the right track. either the 12v source or ground is causing the problem and it can be a loss of contact anywhere from the source to the ground (socket included).