Is there any way to "key" a new stereo for a 2006 pontiac G6 without taking it to the dealer? will changing the cables fix this issue or will I still have to take it to GM to get it keyed so it will work?

Unfortunately the stereo is tied into the security system so it's off to the dealer.

I called a car stereo place about getting a different stereo, and he told me that the stereo would work because they give you the cables/wires to connect -- I am skeptical despite the fact that he ASSURED me that I would not have a problem. Just need to know before I actually spend big money on a new stereo and then have to take it to dealer for additional cost.