F1-F2 Brakes the same?

I Know the drums on a F2 have eight lugs but are the backing plates and brakes the same for F1's and F2's?

 

F-2's are 12", F-1's are 11. AND the F-2's come in two flavors. The early ones are Locheeds and are a variant form of the '39-48 Ford style brake. Late are Bendix, like almost all drum brakes of the fifties and sixties. I don't know year of the chage, but 2 11/16" adjuster nuts on back at 2 and 10 o'clock=early, star wheel adjuster and big anchor bolt at 12 o'clock=late.

 

Bruce nailed it as usual. I'll only add that for the 3/4 Ton trucks, the change to Bendix style brakes occurred in '53 with the F250 model designation (change from F2).