Yeah, computers tend to be the issue nowadays. So many systems are starting to get tied together into one computer that's it's hard to transplant a powertrain with independent control. Just about every car now has wheel speed sensors for ABS/Traction control, body control modules that run windows/doors/maybe even gauges, etc. If you want to pull a modern powertrain you almost need to pull ever wire out of the donor car as well, at least until someone comes up with aftermarket solutions.
