I have this PIE (Precision Interfae Elec.) line output converter to add RCA outputs to the stock HU. IT has 4 wires that need to be connected to somewhere in the HU harness...it has a green, blue, yellow, and gray wire and I used it on my previous car with the stock HU but don't remember which wires connect to which. I was just wondering if anyone knew where these wires connect to or do i just match the colors up? thanks.