Yes, if you are changing from small to big bolt pattern you must use the entire brake set-up. I put 11" C-Body brakes on my 69 Barracuda with cut down C-Body axles and it worked great!
I’ve done the same thing a few times. The entire drum assembly needs to move over. I also did an 11 inch swap on a couple of cars. Also the big disc swap as well. Gotta love them Cordoba brakes!