What PARTS did Hurst and Chrysler put in the Super Stock Barracuda & Dart not in other factory cars

RS23VOA said
What brakes would these be? Or were the rotors and hubs redrilled?

Rotors and hubs drilled (originally when manufactured) for 4 1/2" pattern.

Brake setup was used in '66 trans am a-bodies. Tarozzi helped a little bit on that after hours project.