Remember: Disc brakes are standard equipment from 73 up only!
For all Mopars in general:
A-Bodies with factory /6 had 9” Drums, V8 A-Bodies 10”. Almost all swiss built A-Bodies were equipped with front disc brakes. From 1966-1972 we are talking 4-Piston-Pintype-Calipers! From 1973 up, almost every A-Body build had 1-Piston-Slidertype-Calipers.
The standard configuration on B-Bodies was 10”x2,5” drums front and rear. All the real muscle cars had the much better working 11”x3” up front and the 11”x2,5” installed in the rear. Disc brakes were an option from 1966-1969, all with 4-Piston Calipers. From 1970 up, 1-Piston-Pintype-Calipers were installed from factory.
The big C-Bodies always had 11” Drums! But be careful with the width of the brake shoes! 2 ¾” and 3” were available in the front. 2” and 2,5” in the rear. Optional disc brakes had 4 pistons.
10”x2,5” was the all-around standard drum size in E-Bodies. All real muscle cars were equipped with 11”x3” in the front and 11”x2,5” on the rear axle. The optional disc brake for those bodies always was a 1-Piston-Pintype.
There were no disc brakes in the rear until 1978!