I guess the first question is auto or stick? I think if stick you need to change the clutch (good idea anyhow). If auto, ask someone who knows. Differentials don't change, although turbos usually have a different rear end with lower gearing (cheater way to make it faster).

Regardless, it's not an easy swap. Quite a bit of the electrical harness would have to change, as well as vacuum routing, and that's inside the car as well as in the engine bay. Most people would advise just selling your car and buying the turbo you want. I would be one of those people.