The kit's rear brake package is the same as found on the '94 Cobra, meaning the rotors are vented and are a generous 11.65 inches in diameter. | 
In this shot, the e-brake cable and braided flex lines are attached. You can see by its proximity to the damper body why the e-brake actuation bracket had to be reshaped to clear. | 
A final look at the rear binders. Though not as visually impressive as the giant Shelby stoppers up front, they'll certainly be up to the task. Once the project is further along, some quality time will have to be spent adjusting the proportioning valve so the braking loads can be properly accounted for. |
This simple-looking contraption is a handy tool for directly measuring available rim and tire space under your project.
One For The Toolbox
We originally hoped to use FRPP's factory Shelby rims (PN M-1007-S1895) on the Fox 500, but due to the shortened rear axle and extreme outboard positioning of the beefy GT 500 calipers, it became obvious we'd have to go to plan B and order a custom set of wheels. In terms of backspacing, we also have to be wary of the relatively outboard positioning of the front and rear coilovers.
Along the way, we found a useful gadget to get a handle on appropriate rim dimensions and backspacing/offset, along with some idea of front and rear tire sizing. With the Wheel-Rite Wheel and Tire Simulator by Percy's High Performance, we determined that our Fox 500 can use plenty of negative offset-a deep-dish rim-out back but requires some serious positive offset up front, more like that of a front-drive car. Stay tuned for more on the wheel saga.
The vertical adjustment sets the desired rim diameter, while the horizontal "T" is separately adjustable for rim width and backspacing. The wire on top is bent to shape over a desired tire profile. With the Wheel-Rite assembly bolted in place, it is then rotated to check for interference with suspension hardware and the inner and outer fender. This shot is for illustration only. To accurately check for any clearance issues, the suspension must be at proper ride height.