There is two (or three) people making repop caliper brackets (but not from
https://www.rockauto.com ). That year, the calipers are the same as FMJ’s, but brackets are about 3/8” taller (for the ¾” wider rotor).
Also, the mounting bolts are also longer – so if grabbing the brackets, keep the bolts and keep ‘em together. Those longer bolts are a non-popular size and can’t be obtained from a hardware store and haven’t been available from Dodge for decades.
With that said, there two different version of B/R calipers/caliper brackets. The pin type and slider type. The slider type is what FMJ’s like because the caliper is the same and makes for a quick clean swap. The pin type calipers require different hoses (none of which easily fits an FMJ) and is lot more work to fit onto an FMJ (more suited for older A, B and E-body cars).
For the cost and for the importance of brakes working when you really
really need them to work – I wouldn’t reuse a 40 year old brake rotor.
The spindles are a popular item that will always be in need (curb damage, not keeping wheel bearings repacked with grease timely, etc.) so if able, I would grab both spindles and do something to keep the greasy side from rusting on you.
If it has 10” rear brake drums, I wouldn’t spend any time on them.
If vehicle has 11” rear brake drums, then yes grab ‘em. If not to use, then they are worth your time to sell online.
It does require removing the differential cover and cross pin to remove the C-clips. Then both axles will pull out. Then remove the 5 nuts per side, brake lines and parking brake cables (which is easier to disconnect cables at frame). Keep the drums/backing plates/brake shoes/hardware all together.
If car has 11” drum brakes, it might also have a 9¼” differential – which some people like to grab (considered to be a poor mans Dana-60). It won’t fit an FMJ without modification but does fit most newer B and C-bodies as is. Get some axles made, shorten the width of differential and move spring perches over a bit, it will fit right into an FMJ and might be last differential repair you might ever perform. Chrysler is still making parts for them (used in full size pickups).
An 8¼” differential cover is oval shaped and uses 10 bolts to attach it.
The 9¼” differential cover is square shaped and has 12 bolts to attach it.
It sounds like I might just drive the car a few years until something happens to it, then sell off parts - but I guess that depends if you have space.
BudW