I have an 84 Troopie HJ47 which I bought in 1996. I had it turbo-charged in Melbourne, and was reasonably happy with the 2H that way. It is still an indirect injected engine though, and it is OLD diesel technology, no matter how recent the re-build. I have had the truck in the US since 1997, and in 2000 I put a brand new Vortec 350 in. I LOVE my 350, and the fuel economy is essentially as good as my turbo 2H was on the freeway. Around town I only get 14 MPG, where my 2H got 16, but with the cost savings on petrol, it is by-far cheaper to run than diesel.
I use the Chevy compressors to run my factory air con and power steering, and I mounted the 350 to the front of my factory H55F 5 speed. I put 3.73 gearing in the diffs as well, and at 80 MPH she is turning over 2700 RPM. With the cruise set at 80, and the air con going, I average 21.5 MPG driving from Santa Fe to Boulder. The best I ever got with my 2H was 24 MPG, but that was at 65 MPH (which was about her max speed without over-temping the exhaust).
I can now get parts at any parts store, I have more power than I could ever use, and I get the beauty of a Vortec under the bonnet(c: I hope this helps.
Cheers,
Josh