Before getting a supercharger
 

I'm saving to supercharge my 00 GT and want to know what I'll need to upgrade besides the supercharger system itself to ensure the car can handle all the new found power. Everything is stock except a CAI and Exhaust (cat-back). Engine has 160k on it.

I would be very nervous about putting a blower on an engine with 160K on the clock - you're putting a LOT more new strain on a motor with a lot of miles. If you want to risk it anyway, get a larger pulley that will pull no more than 5 - 6 pounds of boost through your engine. Any more is a much bigger risk of failure.

As for other stuff you'll need, one step cooler plugs, larger injectors, heat exchanger, higher volume fuel pump.