Would any of these work on a 71 Challenger?

I always thought that a Challenger uses a 9" booster but SSBC has a 7" booster listed for it http://www.ssbrakes.com/products/detail ... &year=1971 or a 9" listed for it http://www.ssbrakes.com/products/detail ... &year=1971 . Would either one work on it or a 8" booster as well? Thanks