The VW TDI engines are good, I' have two in the cars and had another before these.
I believe people are putting them in Jeeps, so someone has already figured out rear wheel drive transmission options. They've had stand alone computers for a while too I believe.
The 98 I had, ALH engine, with a tune might be a good choice in a light AD truck, the 1/2 ton. I got 50 couple MPG in the car at about 3,000 lb and it would really get up and go, nothing slow or weak about it.
Also have an 05 BEW and it may have more power (also tuned) but I liked how the ALH drove more, felt like better low end torque, more tractor like.
The BEW engines can have cam shaft issues, and expensive injectors. The ALH is a lot of bang for the buck and still affordable to work on (not that you need to much at all).
If you want a new engine suited to the 1/2 ton this would be my choice.
https://www.cummins.com/engines/repower
