Should be 2.73's stock. Crawl under the back of your car and check the differential cover. There is a small tag on it that will say something like "2L 73".
Most people here will say that 3.73's are the best gears for your application. They take some getting used to but I wouldn't trade em.
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'96 GT
5-speed,K&N air filter,Roush Cold Air kit,80mm MAF,Mac Cat-Back,Mac Pro Chamber H-Pipe, FMS 3.73's, FMS 70mm TB, Steeda Tri-ax, March U/D pulleys
T-Bone's '96 GT