...I'm in the process now with this. I'll have the info in teh next two weeks or so. GM parts and accesory division is looking into making this an accesory. The mechanical part is easy. The wiring is under review. I should ahve warranty info as well. ..and there is a core charge.
You would get a complete diff replacement. It's cheaper than to have someone take your aprt, drill for the wiring and than put it all back together sealing it properly. So the part number that I hope to have soon will be for a new diff with core part #, dash panel, module, wiring harness., and warranty info..oh yeah, cost too. I expect about 2K with labor. I'm hoping for $1500 to $1800 out the door with full warranty though.
...to be clear, this info is second hand, but from what I consider, a reliable source.
