envoy wiring harness suggestions

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. I used the application guide on this site but I'm wanting a professional's opinion. The truck has Onstart (but don't have subscription) and it doesn't have Bose. 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...

GMOS-01 should do the trick if you are sure it isn't bose. even though onstar is not active you still need the harness unless you want to rewire everything. and you will need to buy a separate steering wheel control adapter if you want to keep them.

soundnsecurity wrote: GMOS-01 should do the trick if you are sure it isn't bose. even though onstar is not active you still need the harness unless you want to rewire everything. and you will need to buy a separate steering wheel control adapter if you want to keep them.

Yeah, that's what I figured.  I e-mailed Metra to find out what steering wheel control I will need for my radio (Panasonic).