Mopar Abodies used Kelsey - Hayes (KH) disc brakes from late 1964 through 1972. These discs feature a 4 piston caliper and solid 10+" rotors.
The factory disc 1964-72 upper control arms use a different ball joint than the drum setup. So you need to swap in the upper control arms from the K-H disc car (donor car).
The K-H setup now has inexpensive rotors available in the aftermarket from Centric. Look at the partstrain website for Centric Ctek rotors for a 1969 - 71 Abody. These were recently listed at $21 / each. You must reuse the rotor hat from the original wornout rotor, as these are not readily available (AFAIK). The calipers are available rebuilt at Rock Auto, and many other websites. Also, you can buy rebuild kits, including updates to install stainless steel sleeves in place of the iron (easily pitted) factory sleeves.
You can use either a factory proportioning valve block or substitute an adjustable proportioning valve.
The master cylinder for this conversion should be one specified for a disc brake car. There are several available, depending on whether you have power or manual discs. I like the manual setup with the 15/16" bore.
Using this setup allows continued use of the factory SBP wheels, which is a savings compared to the '73-76 LBP conversion ( in this conversion you do get the advantage of more aftermarket wheel availability, but you still must buy the wheels.) Another area sometimes overlooked in the LBP conversion is the need to swap in a different sway bar, if your Abody came with a factory SBP sway bar setup (mine did, as it is a 1971 factory 340 Duster, with a sway bar included as factory standard equipment). All of these inclusions in the '73-76 conversion drives up the overall expense compared to sticking with the factory SBP / factory sway bar setup.
Coys and Cragar, among others, as well as Centerline, make very nice SBP aftermarket wheels, or you can also go to a wider factory rallye (many vendors including Summit sell factory repro rallyes) or steel wheel if that's what you are after.
