you can usually wire into the rear left channel speaker wire. Wire that into RCA jacks and put that through to the amp. Thats the way i did it in my explorer. I dont think the stock systems carry a subwoofer pre-out. The sound is alright, but is no comparison to an aftermarket unit with pre-outs.
1998 GT black
Flowmasters on Pypes Off-Road X-pipe
Steeda Double Hook Clutch Quadrant, Firewall Adjuster and Adjustable Cable, King Cobra Clutch
Eibach Pro-kit, Mach 1 tokicos
Steeda Tri-Ax Shifter, BBK UCA's & LCA's, All polyurethane bushings and isolaters
"I don't know which is louder...my exhaust or my stereo..."