Project proceeding...
I received an email back from the UT Dept. of Enviornmental Quality, Div. of Air Quality Mobile Services and Transportation Section
1. If the original automaker manufactured the car with the option of a diesel or gasoline engine, then this is allowed. The diesel or gasoline engine must match the make of the automaker. In your case you stated the diesel engine would be 1995 or newer being fitted into a 1995 vehicle without OBD II standards. This is fine.
2. The diesel engine must pass the "Inspection and Maintenance" I/M tailpipe test in the county in which the vehicle is registered. Thus you must install a 1995 or newer diesel engine in good condition, but be sure to have it tested for tailpipe emissions at an I/M service station.
So, the project is a go. I've tentatively sourced a white LWB 95 Classic for under 1k. I'm still waiting to get more clear/ detail pictures back. Appearantly there are some electrical issues with doors, seats, mirrors... Big shock. As long as it's clean with a spotless interior and very minimal rust, I'm down.
It will still be a 300Tdi with a diesel R380 and LT230. I decided I'll probably do 4.11's instead of the 1.4 box too.
Also my friends at GBR offered to give me up a couple axles which will be sewer capped. I'll start a build thread when I get going.