If a '99 GT is out of your range, I would get a '94-'95 5.0L GT and spend the difference on heads or other upgrades. Or maybe instead of a '98 GT, look for maybe a used '96 Cobra. If you're planning of modding, I would stay away from the '96-'98 GTs, unless you are ready to drop some $$ after the price of the car.
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'97 Cobra, K&N, Flowmaster, subframes, 4.10 gears, Steeda Tri-Ax shifter, Steeda G-Trac 3, Cobra R wheels w/ Goodyear F1s
My Ride