So I just got finished mounting my fog lights and running the harness through the engine bay to underneath the dash. My question is: Where do I plug the yellow wire? I can't plug it in to the 2nd from right accessory (fuse box) because my alarm is plugged in there. Where else would it work?

 

BAMP!

 

what year civic do you have? if the plug fits where you have the alarm plugged for a 12v constant source i would suggest moving that somewhere else and putting the plug there if it fits and find another spot for the 12v constant for the alarm.