The subs should pose no significant problem, with the exception of possibly having to use actual speaker wires for signal as I'm not sure if the stereo has pre-amps. Wish them luck getting the stock stereo out, though. Took me 4 hours just to figure it out. I know there's a guide on the Internet somewhere detailing how to do it, seems pretty accurate in hindsight.

No clue on the door locks as I've yet to replace the door speakers.