I'm sure I could get the engine to physically fit without too much grief, Ive done more extreme conversions.

Just fitting an engine has never been hard, and the EXTREME simplicity in the form of wiring on a Mercedes diesel (at least pre CDI) would make its swap into anything easy compared to there swaps Ive done.

Warning unqualified assumptions ahead:

For example, due to the fact that the starter is on the engine side (rather than on the tranny), it would PROBABLY be pretty easy to make an adapter plate out of simple old 1/2 or 3/4 " steel to go between the engine and bel housing of the new trans, this would require the torque converter to be spaced out from the flex plate an unknown amount and it is based on the assumption that the starter ring gear is on separate flex plate that bolts to the crank and is not part of the torque converter. And that the general component layout is like 90% of other cars on the road that I have seen.

Also the 2 trans bell housings must be about the same size, but the spacing out of the trans should take care of starter clearance issues.

Now that being said, I would NOT attempt this unless I had all the time in the world and free parts (which I don't for the most part). It would be better to simply put in a 617 compatible trans.