04 upgrade questions

[Kingslayer]

This seems to be a somewhat popular project around here. I have the 04 Moon and Tunes which is, of course, lacking the subwoofer. I also have the single CD player w/ XM.I would very much like to put the 05 sub in my 04, along with a factory 6 disc changer w/ XM.Has anyone done this and have a parts/price list? Is the wiring for the sub there in the 04, if not what do I need to do/mod to get this done. I'd like to use all GM components if possible.I don't want to lose XM capabilities with this and hopefully the XM components are seperate. I don't know as I've only had the car 30 hours and haven't torn apart the dash yet so any info there is helpful also.Thanks for your time guys, it's appreciated.***Upon doing some digging here I see that XM is out with a 6CD changer so I'll stick with my single. (correct me if I'm wrong)***