07SSCobalts

How's it going guys? Just bought my Cobalt (2007 SS/SC w/OnStar and Pioneer system) a few days ago and first things first, upgrade the sound system. I've been searching for weeks and haven't had much luck on what exactly needs to be done in order to have the stock speakers working (minus the subwoofer, not important since I'm upgrading) along with my subs without keeping OnStar/door chimes. I'm not worried about keeping OnStar, door chimes, or steering wheel controls. Can I just use the standard wiring harness from Best Buy for the Chevy models, wire it together and plug it in?

TIA.