There is a guy on the wrangler forums that did a 89 or 88 YJ, swap was dead easy, he even has the part numbers for the adapters and what not. Got it out of a delivery truck that rolled, $1500 for the wrecked truck, pulled the engine and sold the aluminum body for $1200 or so. Even uses the stock gauges and ignition switch. However the AX5 did not last longand the AX15 was getting replaced last time I read about it.
If I even considered a diesel swap... Id get a more powerful tranny too. If i didnt break it off the bat, i would mod the diesel for lotsa torque. Bye bye ax15....