What year gm car is it? they changed some colors in about 93'
The older style had a separate connector with an orange(batt const.) and brown(dimmer control) wire. then there was a black plug with a pink(power ant) black(ground) yellow(swicthed 12v) and grey (dash illumination) the other two connectors one blue and one white were the speaker wires. The newer style gm's have one big black connector and two small ones one black and one blue with some color changes the red was (switched 12v) and the white was (power ant.) light brown was (dash illumination) dark brown was (dimmer control) and batt constant was orange and orange with a black stripe. Now these wires im talking about are the colors on the car harness side. I hope this is some help