im in the process of putting together/back together my 88 k5. one weekend all the lights work the next they dont. the only thing different from one weekend to the next is that i installed a new set of taillights and installed a stereo. there wasnt a stereo when i bought it, but the clippings of the old stereo wires were in the dash and i ran new speaker wire. now the 2 wires that i have for constant + and for the -, if i accidently touch them together, the lights go on. even though they are + and -. could a headlight switch have a good setting for the headlights but not the parking lights? could i of have pulled a plug off or something pushing the stereo wires back into the dash? thanks for any help.