Try this first:
viewtopic.php?f=18&t=3968Yes you can turbo it - I have done it and a few others on here have too...
From memory you need:
Turbo inlet manifold
Turbo exhaust manifold (with turbo)
Sump
Injectors (preferably 100PS)
Exhaust downpipe
You may need to cut the flange of the middle box and weld it 90 degrees around
The turbo oil feed/return pipes
And a different injection pump is advisable still a bosch one but either the 146 or 145 from a late 76PS van. (Last 3 digits of the long number in small text on the side)
You are turboing a non turbo engine, so you dont need to advance the injection pump which you would have to do on a turbo engine (as the camshaft has different timing)
But whatever you do feel free to ask questions!