If the colors on the the 1984-1986 diagram I posted aren't right, try this one http://www.the12volt.com/installbay/...74&type=Stereo.

These are for the 1983 Mighty Max truck, but I find that most manufacturers still use the same wiring colors for all vehicles in a given year....


And about the constant wire......it is true that lots of cars don't have a constant wire. So you can get a test light and find out where a live spot is in your fusebox and connect the wire there.