1995 vw vr6 gti

I just purchased a 1995 vw vr6 gti that in my county is the only year in which emissions are only visual.  the car was bought at an auction and is going to be a project car.  As far as engine and trany what internal parts should be replaced and upgraded?  what parts should not I not go cheap on?  Also what brands should I go with?  If anyone has any input I would greatly appreciate it.