Not sure if it is the difference in wheels. It is my understanding that the base v6 has a different steering rack than the GT's. Not sure if maybe someone simplified it and maybe all base models come with 17" wheels. IDK.
Whipple, 3.125" pulley-Comp NSR's-Meziere-Pacesetter L/T's+Outlaws-Level 10 trans-PI 3400-PH driveshaft-Auburn Pro LSD-Richmond 4.10's-CobraJet springs-Viking shocks-BMR control arms, panhard, rear sway bar-and a bunch of other really cool shit