well after i replaced my wiring harness i forgot witch wires go to what all i need to know witch ones go to power o2 sensor and dimmer its for the auto meter air/fuel...i know iknow its usless but i like the lights and gives me a wild guess on how shitty my car is running lol

 

from memory I think this is right.

purple = o2 sensor
black = ground
red = illumination
yellow = 12v

but there is this wonderful site called autometer.com which has all of the wiring diagrams for every gauge they available. amazing!

 

im lazy i dont feel like looking lol j/k