Can i put aftermarket tail lights off a eclips on a 3000gt?

I think it might be the headlight relay but i do not know where thE switch is located therefore can not replace it. where is the relay located?

When Head lights are on the rear tail lights (running lights) do not work. or come on. Bulbs are good, wiring and connections all seem to be good.

1990 chevy silverado. the tail lights stay on at all times. but not brake lights

I need to put in a shirt tail hem in a party dress. Do I need some kind of sewing machine attachment?

My dash lights and tail lights quit working after a friend anstalled a stereo in my 1997 plymouth beeze i checked the fuses wha else could it be?