for those who have installed their own aftermarket head unit....besides the unit itself, wiring harness and installation kit was there anything else you had to use? I had a guy at a local audio shop telling me today that you have to have some adapter in order to play an aftermarket radio that was 200 bucks!!!....TIA

 

Depends on what factory unit you had. If you have steering wheel controls or onstar you might need the other harness to make them work correctly

 

There are hardwire kits out there that give you the convenience of keeping the factory wiring intact, but you lose all the chimes and turn signals. The adapters are for vehicles equipped with OnStar and keeping the chimes/signals.