I have my wiring harness that is specific for my car and the connecter for the head unit all has color coded wires that connect to the harness but where I'm confused is the (Black) Ground wire. Both connecters have a black ground wire coming out of them so do I connect these 2 black wires together or do I ground them each indivdually to my auto body frame and not let them touch other? I hope someone understands my question cause I need to get this done ASAP!