I noticed when you upgrade the brakes on the Ford Capri barn find to sport or racing the rear just becomes some floating calipers without a rotor. Just a minor design bug but still a bit irritating to have.
Put image up on imgur because the gallery servers are unreliable right now.
Easy fix.
Restore car to stock upgrades.
Reinstall race weight reduction.
Reinstall race brakes.
Brake rotors will be present.
*If you do the brakes first followed by weight reduction it takes them off the car again. Every little helps when it comes to saving weight and going fast! Lol 
Weight reduction bro!
B coz Race CAR!