AIIITE, say instead of a T66 i just wanted something small but would give me a little extra HP like a T3/T4 turbo...How would I go about this?  Like, say I bought a T3/T4 for an Eclipse, is it possible to take that, get someone to bend me the pipes and make it a bolt on for my SL?

Because of the design of your engine(V6) a single turbo is gonna be hard to put on there.  There's plenty of room in the bay, but unless you have a friend with a welding shop and a week to spare(and he's not charging you), making an exhaust manifold for a single turbo is gonna be hard.  Remember, you can't go using aluminum pipes or exhaust pipes you can ge from autozone,  You'll need steel.  But check it out, get the 3.8l from a diamante or a 3.5l from hyundai xg and throw it in.  It *should* fit in, they're the same 6g7* block.  But if you absolutley want forced induction, get a supercharger.  Turbo may seem the way to go, but it's just a little too hard to get a single turbo on a fwd v6. 

if you're gonna buy a 3000gt and want power, get the vr4 model.  The sl and base models aren't that great for putting down hp and can't handle 350hp very well.  The twin turbo models come awd and can put it all to the ground.  Don't cut corners when buying a performance car, you'll regret it later.