Welcome to the site!
If you "mosey" on over to the AUDIO/STEREO forum, you'll find that it addresses these issues more so than here.
Not to say someone will chime in. Matter of fact, there is a thread here right now about the wiring of the factory subwoofer (Audiophile). Here's that link:
You could send a private message (PM) to one of them and perhaps get a quicker answer.