THat setup was just dummied up years ago, I ended up buying the turbo and a few other bits off him a bit later, then he got them back off me a few years ago, no idea of the current status but it never acutally ran.
Cunning Stunt still hasnt payed me back actually, now that i think of it.
It almost sounds like you dont know a whole lot about turbocharging, which is fine, but before delving to deep into this subject, and asking to many questions, could i suggest you pick up a book called "maximum boost by corky bell" and have a thorough read?
When i was a bit younger and very curious about the subject i read that book, then read it again, cover to cover, and learnt a LOT.
Its a bit outdated but still the best reference i have seen that covers all the basics. Does not cover anything at all particularly for a Holden six, but at the end of the day there just an engine, the same principles are applied to any engine within reason.
I set up a very basic blow through turbo setup for under a grand using info out of that book, along with a lot of hard knogin scratchin, and it worked reasonably well...Currently on a stand in my shed, the car it was in is long gone, will revisit it one day.
Cheers.