I have a 2011 Yukon SLT with bose. I found a 2012 head unit with the hard drive and an over head monitor out of 2 other Yukons that were being parted out. Got it all for super cheap. I was wanting to set up the RSE like it would if it was fitted with the option. My question is this, what else do I need? i.e wiring harnesses for the RSE from the head unit or whatever?