So i recently got a new work truck. Its a 2011 silverado 2500HD with the 6.0. No onstar, no xm, just am/fm only. not even a cd player or aux port. I want to add a new head unit in to gain an aux port for ipod connection. Is there any option for a wiring harness other than the ones capable of handling the onstar adaptation. I also dont care if i lose the door chime but ive also heard that disabling the door chime causes an error in the system??? Doesn't sound like it would. Any info would be greatly appreciated. Drove over 600 miles today and am/fm only is a nightmare.