Knuckles will interchange between any A/B/E and FMJ body car as long as you understand a couple of issues:

1972 and earlier A body cars need to be upgraded to the larger upper ball joint in order to use the big bearing knuckles.

1973 and newer B body cars and all FMJ cars use a taller version of the big bearing knuckle.

As for your brake issue: Slider and pin type brackets will interchange on the same knuckle. Small bearing and big bearing hubs do not interchange.