I think Ford offered an N/A DI 7.3 as well as a turbo IDI 7.3 in late 94 but may be mistaken.
What year(s) were the 7.3 DI turbo non intercooled?
As far as the jeep thing goes, the 6.2 is so close in size to a SBC it makes for an easy swap and above all it's *cheap* (compared to other options)
it has the Chevy bolt pattern so bolting a tranny to it is easy.
The 4BT Cummins is a great unit but (too) big and heavy.
The IHC engines (6.9/7.3 IDI) could be made to work, but are much heavier that the GM engine. On the DI, the electrical control system would be a major project alone. (It'd be cool to see a PSD in a jeep though...
)
Mose of those small foreign made units (Isuzu, Kubota, Perkins, Lister-Petter etc) are nice units as well but parts availability, tranny mounting concerns, and cost usually make these unfeasible.
Bang for the buck, the 6.2 is the best bet.
but maybe I'm slightly jaded... ;p