I am going to be putting in a head unit in a 2002 GMC Envoy. Right now the factory radio is in it and I need to get a harness to hook up my new one. The problem I am having is that there are so many different harnesses out there and I don't know what I should use.

The truck has Onstart (but don't have subscription) and I don't think it has Bose (no Bose logos or anything). It looks just like in the picture below...


So what harness should I use? I know there is the GMOS-01 and GMOS-04 by Metra but what one would I need? There is also a Scosche DCGM09 that is cheaper but I don't know if it works with the truck. PAC Audio has some as well but I don't know which one would be the best.

Any ideas or preferences on what I should use?

P.S. - It has steering wheel controls which I would like to keep as well...