whatever you do, DO NOT USE an amp'ed player with the factory amp, it will fry.
You have to by pass the amp, unplug the harness from the amp, splice into the wires, and run those splices back into the harness from your amp.
you'll also have to splice into power, ground, dim, etc. on the harness from the old CD player.
I used to have the cables written down, but I went back to stock and must have deleted it