Is it possible?
 

Is it possible to put a 993 TT engine into an '84 TLC? Couldn't find any threads that covered this. Thanks

Yes, although it's not a bolt-in by any stretch of the imagination. Locally, we have a 1972 with a 993TT motor in it. One of the bigger hurdles is fitting in the G50 transaxle. You'll need to mod the tub and either go to the later style of torsion bars or convert to coils. The changes will extend from the pedal cluster all the way back to the engine sheet metal. But with enough time and money, it can be done.