Why would you attempt to fabricate a turbo from junkyard parts instead of going with an already made and proven aftermarket supercharger (which would probably save you quite a bit of cash)? And why would you go with a twin turbo, instead of a larger single turbo? And I don't remember Volvo or Volkswagens ever using the T3 or T4 turbos (could be wrong here, not big into German autos)...