For those who didn't think it was necessary for the $150 harness from Metra or BestKits to relocate the factory radio, when installing an aftermarket Head Unit in GM'* 99 or newer.............here is the proof.
This is NOT necessary for all GM'* after 99, it is vehicle & year specific. If you are not sure check with your local stereo shop for the correct harness or check out Metra'* website.
As I mentioned before in previous posts, If you do not relocate your factory radio and use the proper harness you will lose a lot more than just your door chimes...........Possibly your SRS (Airbags)
This is from the Velocity Motors website from one of the best installers in the industry (Jeff).
This is common knowledge in the industry with experienced Installers.
Relocating the factory radio in certain GM models is necessary to maintain vehicle integrity.
For this link click on the second section. This is a How To on relocating your factory radio.
You can also find other useful info at
Hope this helps,
310k Licensed Auto Accessory Tech (Installer)
First Class MECP Certified