That was me, and while the TDI is great in the car, (with the chip it's much better than the VW gas engine) I would not bother to swap it in a truck.
But depending on your needs it could be OK? If you want good mileage, almost acceptable performance, and never haul anything, then the TDI may be fine in an S10.
If you just want a VW diesel, buy the Jetta and drive it as is, save money and lots of time.
And you can still fit a bunch of stuff in a Jetta, I've tried. like these truck parts, 3 fenders, two inner fenders, a hood, grill, and a few other parts, they all fit in the car, and one more hood on the roof rack, and they are 2 ton truck parts...
I have also had a Roadranger 10 speed in the trunk, and even a Dana 60 on the roof rack (not at the same time).
Personally I would go for a bigger/different engine in a truck.
What do you hope to gain by doing a small diesel conversion in an S10?
Grigg