Has anyone looked into if swapping an 8 speed transmission into the earlier E70s is feasible? I'm doing some preliminary research using my 4.8 as a reference and a 50i as the donor. So far, the bellhousing bolt pattern appears to be the same. I'm guessing overall length is close as well - the rear driveshaft is 1mm different in overall length, but of course that incorporates the transfer case as well. The E70 has seen a number of transfer cases over the years and it's another challenge to address - is the bolt pattern and splined output shaft the same between the 6HP and 8HP? If not, then the transfer case that goes to the transmission would have to be used and I'm not sure how that would integrate. From what I can tell, it does look the same (at least the bolt pattern). Once the mechanicals are addressed, we need to worry about the electronics. I've heard, though not confirmed, that the 8HP uses FlexRay for communication whereas the 6HP uses CAN bus. My suspicion is that while this might be true on F-series vehicles, the E70 likely retained CAN bus for its 8HP implementation. Assuming the message format is the same, I suspect the transmission may be plug and play... As far the immobilizer is concerned, I have the equipment to synchronize the ISN on both the 6HP & 8HP. It looks like the CAS is shared between 6HP & 8HP, so I again suspect it can be made to work. Any thoughts? Does anyone have wiring diagrams for the 8HP by any chance?