Jeffery Zweigle

Hello everyone. So a year ago I thought I would install factory navigation to my son' non navigation 05 tl( a birthday present). So I found a guy totaling out a factory nav 05 tl. I had to pull all the parts, and I did. I took the CD changer, and the harness, cause I guess I need it for the gps antenna?. I took the nav unit, all the harness clips, and a few extra interior parts. The guy told me 50.00, but I felt I was taking advantage of a rare deal, and gave him 100.00, lol. I started working on it then COVID hit, and was stumped as well. I am looking for HELP. I have purchased a double din dual receiver, and have that mounted very nice below the factory nav. Can someone please tell me if I grabbed everything needed for the nav to work my car has factory xm.and steering wheel controls. And what is the best way to get the nav/ and aftermarket receiver to accommodate each other, as far as harness wiring, and get my son's HVAC system running again. I really appreciate the help, jeffrey