I had to learn a bit about B body disc brakes, so here's a bunch of useful brake info. Some of this also applies to other cars.
I ordered an MBM Brakes master cylinder and booster kit from Mancini Racing. This includes the master cylinder, brake booster, firewall reinforcement plate, and linkages to the pedal. These are all parts that are needed to convert from drum brakes to disc brakes. Item MBMBCK8536-1 & MBMBCK8536-2 appear very similar in the photograph and item list, and it took me a bit to figure out which item number was correct for my application. The item fitment description lists the wrong change over year for B bodies, and that added to the confusion. It says that 70 B bodies are the same as 70-74 E & 71-74 B, but this is incorrect. 70 B body is actually like the older 66-70 cars. B body didn't update until 1971. The difference between these two items is the firewall reinforcement plate. MBMBCK8536-1 comes with the 1966-1970 B body firewall plate, while MBMBCK8536-2 comes with a 1970-1974 E body & 1971-1974 B body firewall plate. I'm building a 1970 B body here, so I bought the MBMBCK8536-1, which strongly resembles what the factory would have used in a power disc brake car. Their photo provided for MBMBCK8536-2 does not resemble what the factory used in E bodies, so I would be reluctant to use that in an E body. (maybe their picture is wrong?)
