I used the BTAH extension cable and spliced those wires onto my existing stock speakers.
(i used a volt meter to test which of the six input wires went where on the plug for the back of the bazooka, and used the handbook to find out what those wires did.)
(wires by color)
GRAY- HI-LEVEL INPUT +
GRAY/BLACK- HI-LEVEL INPUT -
WHITE- HI-LEVEL INPUT +
WHITE/BLACK- HI-LEVEL INPUT -
RED- POWER (12v+)
BLUE/WHITE- IGNITION (12v+)
(that is from memory, so it could possibly be wrong...but its close enough to figure it out)
Now i have my sub in the back of my car, all hooked up, the wires are under the carpets and under the plastic liners and everything works.