I have an 86 Camaro with a 2.8L V6 and a 5 speed manual transmission. The gauges work fine (except gas but I was told that I would have to replace fuel pump for it to work) during the day, but when I turn my headlights on and my gauge lights turn on my rpm gauge and oil pressure gauge go crazy and they also jump around a lot if I use my blinkers. Any ideas?

definitely a case of short circuit. i mean the gauge lights and headlight pass through same flooring - wiring. there may be come crossover which is torn out. make that check

Ok thanks I will dig around in there a bit and see what I can find.

IIRC there's a ground for the headlights if the front on the passenger side.