Home built rack and pinion+ coilover build.

A rack that is four inches narrower than a stock Pinto or Mustang II rack will most likely get the bump steer very close at the outer ends of travel, and would move that outer tie rod end in far enough to clear the rotor on a standard Wilwood setup. I don't know how much offset difference there is between the Wilwood kit and a factory A body disc brake kit. If someone could measure from the inner rotor surface to the center of the lower ball joint grease zerk, we could figure it out.
I do know that the inner tie rod would need to be within a 1/4 inch of the Wilwood rotors with a four inch narrower rack. The stock \Pinto/Mustang rack has an inner center to center length of 25 inches.