I have an 2001 Outback Limited with the premium sound package (The 8 speakers and under-seat sub, not McIntosh). I have and amp and two 12"s from my last car, which I've wired to the battery and grounded to the frame. I would like to know if there is a way to pull line signal from the wiring to the under-seat sub and connect to my amplifier. I am pleased with the sound from the stock stereo and would prefer not to buy a new head unit if possible. If anyone knows, or has diagrams of the harness pin-out that would be helpful too. Thanks.