If you already have 73+ disk brakes on your car, all you need is the calihappen to brackets for the 11.75" rotors and the rotors themselves. Calipers are the same and can be reused. As mentioned, Cass sells the 11.75" caliper brackets for $100 now. Too easy! I had to find mine!
Great upgrade though, much better stopping power and still all off the shelf stock parts. Only other thing to consider is that you need to have 15" rims to clear the 11.75" brakes.