Hey, welcome!
As you commit to going down this path, it is important to keep in mind the potential for things to go wrong, the need for fabrication, and the importance of sticking to a budget.
That being said, you have a few options (assuming you're looking for more power than the US spec GT provides).
You could go forced induction on your 1ZZ-FE.
You could swap in a 2ZZ-GE (most direct swap).
You could go for a Honda K series.
Those are the most common and most supported. I have also heard of 3SGE and Honda B series swaps.
MonkeyWrenchRacing.com has kits for sale for Celica engine swaps. Definitely check them out.
Let me know what you decide to do, I'd love to see it!
Good luck!
