Right, because the colors are meaningless.

For example: On your aftermarket harness, the ignition-switched power will probably be colored red, and on the empeg, the ignition-switched power is colored orange.

So don't match colors. Match FUNCTIONS, not colors. Each of the empeg wires is labeled with their function. If you don't know the functions of the wires on your harness, you need to find them out (and not by trial and error... you need real live instructions).

What is the make and model of your car?