Rob,
I'm leaning over towards a Mercerdes conversion
http://4x4labs.com/diesel.html
although it looks like I'll have to wait a little for the Automatic adaptor.
My second choice is just droping in a full sized Chev engine, transmssion, and T-case.
I think that the Isuzu 2.2L that came in some S10's are too weak for what I go through.
My reasons for wanting the Mercedes is because they weigh less than the full sized power plants, plus they have a better track record.
Although I could probably work around the full sized flaws if I knew what they were.
I found a mercedes parts car in Vancouver, that I'll be taking a look at in 2 weeks when I'm passing through.