I have a honda civic ex automatic and I am currently putting on gauge faces. I got it all put on but I have a red and black wire and dont know where they go.....one i know connects to the headlights but how?

 

black is ground... black is always ground (except for on ceiling fans, but we're talking about cars)
so you wire the black to a metal spot on the chassis

for the red wire, you should wire it to the turn signal/parking light's wiring. If you wire it to a headlight, if you pick to wire it to low beams, then it won't be on when you have the high beams on, or vice versa) Parking lights are always on when the switch is turned, no matter what beam you're on, so i'd say wire it to those)