OK i did this mod..
I have a 2013 2500HD
I bought a ful harness, a clocking spring from GM for a Denili 2500HD
Note, Even with the correct harness, when connected to the sterring wheel did not work,
So i ended up cuting the harness and saving the "connecter" with some leads left. I extended the cut leads and attached one to ground and the other to a switched on source in the BCM.
Light for the heated wheel comes on.. but I do not feel my wheel getting hot.... so I'll have to investage it more tomorrow...