As I mentioned above, I have enjoyed the disc brakes on my '34 pickup for more than 20 years. Here are some pictures of the installation. Super Bell stopped selling the Mustang brakes and replaced them with GM brakes that won't allow K-H or early Ford wheels. Note how the calipers don't interfere with the wheel.
According to Ron Ceridono in Street Rodder Magazine Super Bell may still have the Mustang brake kits...but they don't have the calipers. Since the calipers are the key to a bolt-on assembly you can search for them. After all those Mustang, Comet, Falcon, Fairlane, etc. guys also need to find them.
This kit was an honest "bolt-on" and NO modifications of my '40 Ford spindles was required. The kit came with the 5X5 1/2 bolt pattern. The wheels need a simple aluminum spacer (not an adapter) 1/2 inch thick. No matter how you mount K-H wheels get the 1/8-inch thick brackets supplied by Dave Wilton to prevent cracking due to a lack of internal "bumps' on flat surfaces. The wheel in the photo is a 17 inch stock 34 wheel since replaced by 16 inch KH wheels.