Funny, your "Family Truckster" build is going through a lot of the same sort of things I'll be doing on mine, it's practically my reference manual. 2WD conversion, hydroboost, aftermarket ECU, etc...
There are several guys running turboed 4.2, and they are getting crazy numbers out of them. One guy is running one in a Chevy Nova running low 9s, there is even a dragster or two.
Here's one guy who put a DCOE patterned 4.2 in, mine will be similar, but I'm actually trying to get the CAD done for the manifold, do a model on a 3D printer and have it cast, this one is fabricated.