Alright guys, so I seem to be stumped. Attempting to address multiple different concerns. Oil Light/ Gen Light key on engine off. I have also noticed no illumination. I removed the gauge, replaced all the 194s as that’s what I had on hand. Re-installed the gauge, sweet going to have lights right? Wrong. Turn the key to on and still no Oil/Gen lights. Shucks. But maybe illuminate lights work now?! Turn the headlight switch on, fuel level begins to skyrocket. What the heck? Turn headlights off, goes back down, but continues past E. What the world is happening? Turn the key off, no change at all. Has to be something I’ve done right? Unplug gauge, unplug all the new bulbs, reinstall gauge now not even turning the key the gauge comes back up, but perfectly to the E mark. I’ve never seen this gauge go to E, so I highly doubt that’s how much fuel I have? I’ve attempted to check the schematics. My biggest concern is the fuel gauge at this point. My pink in, 12V key on only. Grey wire from sender has 0V. Turn the key on, no headlights, and now the grey wire has 12V. I’m shorting the gauge not having the bulbs in? Any help is much appreciated

 

Is the gauge bolted to the dash? If not, the gauge has no ground and it will do all sorts of strange things. Run a jumper wire from the gauge housing to a good ground, see if that changes anything.