I also have an '03 GT and am in the process of selling it so that i can get any Cobra. After being exposed to a 4v, the 2v is really no substitute. If Im going to have a ford smallblock thats got 2 valves per cylinder, I'd rather have a 5.0. If im gonna do a 4.6, its gonna be a 4v. Give me the low end torque of the 5.0, or the top end of a 4.6 4v. The 4.6 2v delivers neither.
JMHO.