I have a 1970 fastback mustang with a 302 V8 and 4-wheel manual drum brakes. I want to convert it to 4-wheel power drum brakes. This is my wife's car which she bought new in 1970. However, her back issues make it very difficult for her to push the manual brakes. I have been looking at a Master Power Brake Booster which says it will work for disk/drum or disk/disk brakes. I called and asked if that unit would work for drum/drum, and they said it would. Does anyone have any experience converting 4-wheel drum manual to 4-wheel drum power?