Sorry folks, this, I am sure has been asked a bunch, however, I am new to the F150 scene. I want to replace my factory six disk in-dash unit with a Pioneer unit (avh-p4000dvd player) on my 2004 F150 (new body), however, I dont want to loose my factory sub-woofer (an audiophile system). I know mustangs inside and out, and when you replace a head unit on the Mach system, you have to have a Pac unit to run the external amps, is the F150 system the same? If so, where can I get the wiring harness. Any help would be great and I am sorry for the 101 type question. Thanks!