Bosectomy?

Looking to change out my Bose system in my 2000 Jimmy without OnStar, and not sure what is involved. There are a lot of adaptors available, and not sure which ones I need. Looking to replace the head unit (mine keeps getting an ERR, and front door speakers (passenger side sometimes sounds blown) maybe the rears, and adding a simple sub/amp. I would prefer to keep the steering wheel controls too, but not sure if that is possible with the other adapter I need. Anyone know what there is to it?

You can.  Sometimes it requires a complete rewire of speakers and such.  pull out the radio and tell me what colors are in the radio harness.  not hard to do at all, just a lil time consuming. 

Thanks for the help. The harness connector is a square that has black on the top with 10 wires and an offwhite on the bottom with 6 wires.

That is the standard GM harness, metra part number is 70-1858.  can pick up the wiring harness at any stereo shop for about 15-20 bucks, or get one at a parts store for about 11.  the Dash kit will also be needed if replacing the factory radio.  metra number is 99-3300.  Pretty easy to do.  just hook up the blue wire in new wiring harness to the blue wire off the back of the cd player and that will turn on your factory amp.

So no Bose specific adapter or re-wire is needed? Also if you know is the factory amp part of the speakers, or is it somewhere else? Looking at getting a set of components for the doors, and wondering where to stash the amp, if I can just use the factory amp (if its a good option, dunno) to power them that would be great, cause I cant seem to find a place to put in an aftermarket amp that will not get over heated.

Thanks for your help.

the factory amp would probably be under behind the glove box. you can put an amp there, also, under one of the seats.  sometimes you do need extra wiring, sometimes not, kinda depends on the system.