Hahahahahahha, that is among the biggest DON'Ts I have ever witnessed!
These cars have been around over 40 years, there have been many things tried, but why upset the balance? If you want a big V8, get a different car. I think a nice modern twinspark is such a nice conversion. Shaker, I see you are from S. Africa, our club's VP is from there, and he has Dawie create some incredible engines. Do a search on JungleJustice's Milano.
There's a few turbos around, and some have been made to work extremely well. Typically see cracked piston liners with the blown 2.0 motors.
Our very own Alfabb has its own engine conversion thread:
http://www.alfabb.com/bb/forums/forumdisplay.php?f=61
Cheers!
Steve S.