Not trying to be rude, but If you want to piece together a turbo kit you might just want to sell your car and buy a Honda, that way you wouldn't be ruining $5000 worth of car if something happens, but to answer your question, (just from what I've read) Your going to be looking for the equivalent of a gt2871. You'll need a different exhaust manifold (cast iron is best) and probably a down pipe. If the turbo you get doesn't have a waste gate then you need an external, DV upgrade, intake tube, tuning, and injectors. Your also right on the edge of needing to replace your rods, and a clutch should be on the list too (and don't get a spec stage 3 they're intolerable). You will be better off getting one of these 1.8T Quattro GT28RS Turbo Kit - 034 MOTORSPORT than buying a used turbo and all the stuff to make it work, but you still will want rods, fuel injectors and tuning, Your talking $3-4k, and I'm not an expert I've just been looking into this stuff for the last couple weeks.