It has always been my understanding that the swap was for 53 to 56 F-100 stuff. I know that shoes and drums ( not the hubs ) from 53 to 66 interchange. I can use the 1966 springs and brake hardware to make my 56 brakes " Self adjusting "



I know the 52 back F-1 drums are different. I know that 57 up hubs and backing plates are different.