jvick, i shall try a stereo shop, not sure why i didn't think of it, i guess i wouldn't of thought they'd have the ability to work with stock stuff, but i guess thats kinda silly.

paul: I'm not sure what you mean by adding 3 wires. I'm actually totally re-wiring it as I don't have a stock wiring harness at all, so basically I'm going straight from the sub to whatever
orange -> left rear (-) of amp's speaker out
black -> right rear (-) of amp's speaker out
violet -> left rear (+) of amp's speaker out
white -> right rear (+) of amp's speaker out
red -> +12 V line, switched (although I may be switching that to the always on as there seems to be a cap in the amp keeping the switched line on even after i turn off the ignition (only stays on when wires plugged into amp
grey -> grounded

I'm basically copying the wiring from http://www.scoobymods.com/forums/showthread.php?t=199 at least I'm trying. One thing though is that in that thread it mentions needing floating ground for the speakers, and I'm not sure if I have that, if it actually matters, or how to test whether I have it or not.

Thanks for any additional help
Brian