Chip,
I do not know what you would be planning to do with one of these and that might make a difference, but one of the big things I would look for is one of the older Dueces with the engine that can burn anything. I spoke with a guy who used 75% used motor oil and 25% gasoline in his fuel tank, and he said it drove perfectly.
The point is, if you are thinking about going off around the world, then the ability to burn pretty much any combustable liquid would be very nice.
Good luck!
Check out steelsoldiers.com, they always have a lot of good stuff on their forum.