made a homemade adapter for the transmission. Did not have to touch the firewall. Nothing else in the drivetrain changed other than the length of the driveline (slightly). Everything else is original. Not finished yet. Need to do the doors and the wind up the winch. Stole the color from a chrysler paint book. Cant remember what year I used. I will have to look up some of this stuff. The baby cummins (from a frito-lay step van) fits right in there no problem. Slight re-arch to the springs to get that giant oil pan from bottoming out. So it looks like it has a 1" lift.