Need some help (Upgrades on me 93 GT)

Just to clear something up for you. A Cat-Back isn't a type of catalectic converter; it's everything from the mid-pipe (H-pipe in your case) back. It consists of the flow tubes, mufflers and usually tailpipes. The most inexpensive way of doing it would be to add converters to your current H-pipe like the ones I suggested in my earlier reply. The Catback and Flowmasters have nothing to do with emissions control.

You do not need to get different pushrods or rocker arms in order to change the camshaft, but doing so will net you slightly better gains and durability...but again, it's not mandatory. Aftermarket roller rockers, though do gain you a little performance in the sense that they're considerably more accurate than the stock stamped steel arms (which can vary in ratio), which will make the most use out of a cam change and their roller fulcrum and tip reduce valve train wear and friction, allowing the engine to rev out more evenly during acceleration. But this can always be done at a later date.

Pretty much any 65mm throttle body would be a good start (although Mac should be avoided due to poor quality) with Accufab likely being the best and most expensive of the bunch. They'll all produce about the same amount of horsepower, so buy based on quality, not performance. The stock unit is 60mm (actually around 59-59.5mm). I'd go with either a C&L or PRO-M 73-76mm MAF calibrated to your injectors. You'll probably best realize the T/B and MAF gains when installed together, so it would be best if you saved up until you could afford both of them.

Anything else you’d like to know?