Aftermarket head unit with stock premium sound amp and eq? December 28, 2011, 06:01:59 PM So I'm thinking of installing the new head unit I got for Christmas with the stock premium sound amp and eq. The unit I have in the car right now has a metro harness to bypass the stock amp (which is unplugged). Following this diagram: http://www.foxthundercats.net/tech/aftermarketpremweq.pdf it looks like all I have to do is plug the stock amp and eq back in, make the connections from the headunit wiring harness to the factory plug, and then wire in two RCA jacks. I had a question on the RCA jack wiring though. It looks like the positive (center) of the right RCA jack goes to the pink wire with the light blue stripe, the positive (center) wire from the left RCA jack goes to the pink wire with the light green stripe, and then both negative (outer) wires go to the black wire with a white stripe? It also looks like the ground wire for the head unit gets connected to the big red wire that used to ground to the back of the stock head unit?