[cobrajeff]

Bill -

Early Mustang (65-66) housings are 50" wide backing-plate to backing-plate. Only the 289 HiPo and GT350's came with a 9" - the housing is "necked down" on the ends where the U-bolts go. 1957 thru 1959 full-size Fords have the same dimensions, width and spring perch mountings. These housings are not necked down, and will come with 11.0" brakes (which can be swapped for 10.0" Mustang brakes if desired).

1967-1970 Mustang housings are 52" wide, and would have a 9" if factory equipped with 390, 428, BOSS 302, and even some 351's.

1971-73 Mustangs have a wider yet housing (may be 54", I can't remember). There would also be a fairly good number of intermediate Fords - Fairlanes, Torinos, Comets, and Montegos that could have a 9" rear end - these housings are wider than the Mustang.

regards,

Jeff