Audio Systems: installing aftermarket stereo system, gm dealer, bose systems

Question
What all will I need to change out my factory bose system. How and what kind of wiring harnesses will I need to keep my steering wheel controlls and my onstar and xm radio.?
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Answer
Why don't you search through the following sites and maybe you can find the parts you and procedures you are looking for:

-  "outfit my car" at www.crutchfield.com

-  wiring harness, adapters and  mounting trims, etc. at  www.installer.com

-  original equipment replacements at www.oemautosound.com

With all Bose systems you must be very careful as Bose is not a conventional manufacturer and most of their products do not intermix with other brand name aftermarket items.

In your case you may need to contact with GM dealer or service people to find out how to keep the onstar functionality.