I want to install an aftermarket radio on an 02 tb. It does not have bose, nor steering wheel controls, or xm. It does have onstar and im not sure if its amped. Could I go to wally world and get the harness adapter and dash kit and use them? Im doing this for a friend. He doesn't care about the chime or onstar. I read somewhere I have to run a new acc wire. Why cant i use the existing one, what's up with that? Any help would be appreciated.