Most of those small diesel swaps use Cummins 4BT's which are found in old bread trucks and other delivery vehicles as well as things like Bobcats, etc.. There are adapters available for virtually any transmission. The downside ... those 4BT's are NOT cheap. You could do a Gen 3 hemi swap for less! As for the engine you mention, I'd suggest you do some Google searching.
Yes it seems the 4BT would be easy, just put my trans guts into a 618 case and it would bolt right up but man those are way to expensive to justify for this swap. Also they are very heavy, much heavier than the ole 318 and noisier than this little bity diesel.
No way on the VW, I have had terrible luck with those for some reason.
