Audio Systems: Replacing Factory Bose amp with Aftermarket Amp, 2006 trailblazer ss, rear speakers

Question
I have a 2006 Trailblazer SS with the factory OnStar and Bose system. I am looking to replace the factory Bose Amp that is located in the rear passenger quarter panel with a aftermarket Kenwood 640watt 4 channel. I am not worried about keeping the Chimes or the OnStar as I do not subscribe to it. I am wanting to keep my factory head unit as I want a system that people can not see since I work in some shady areas on town. Can you just unplug the factory Amp and use the speaker wire from it to go to the aftermarket amp? I also do not know which wires to use to tap into for the RCA converter. I already have my subs installed by tapping into the rear speakers but I again do not know about how to remove and replace the factory amp for the door and dash speakers.

Answer
You can add the amplifier but you can't remove the bose amplifier, the volume from the  Trailblazer radio works from the bose amplifier not the radio, there is also data in the audio lines, you need a module to do that

http://www.oemautosound.com/pc-217-135-pac-c2a-gm24.aspx