Using mustang rotors for 4.5" bc

I was in the same boat with my 1970 Duster that came with the KH brakes. I wanted the bigger bolt pattern but I wanted to keep what was original to he car. Especially since the KH brakes are rare and a 4 piston caliper to boot. However there is a gross reality that goes along with these brakes and good reasons for there removal. From a performance stand point, they aren't safe. The bolts that hold the lower balljoint to the spindles are small and are known for breaking. Also, we all know the upper balljoint itself is smaller then the '73 up part. I wound up changing to the 73 up style brakes and mounted the calipers to the rear to accommodate the 70 style hotchkis sway bar I installed. Minus the upper control arms, Classic Industries sells the conversion for $399. So if you're only interested in a wheel upgrade then the Mustang rotor with some machine work will work. However, if your wheel upgrade is going along with other performance handling upgrades then keep the weaknesses in mind. Glad to see this write up though. I was wondering if anyone else besides me had discovered that Ford used the same brakes.