Car Stereos: Need for an adapter, factory wiring harness, factory warranties

Question
I recently purchased a 2008 Chevrolet Colorado that only has a standard clock radio. I went to Best Buy to have an aftermarket unit installed with a CD player and was informed that I would need an adapter secondary to some computer functions running through the radio. Can you please educate me on this and if putting this adapter in would there be any negative impact on the vehicle warranty. Thank you.

Answer
Normally, when installing aftermarket stereos, there are two things needed.  First, you need a faceplate adapter that lets the aftermarket unit fit the OEM hole where the original radio was installed.  Second, you need a wiring harness adapter that lets you hook the correct wires from the aftermarket stereo to the factory wiring harness without having to cut any wires.  All of this is totally reversible, it does not affect any factory warranties.  Hope this helps, Scott