Check the offset of the pinion on the 8.8 Ford. I was thinking of putting a 57 Ford 9" in my Dart but the pinion is centered on it where the Mopar is offset 1 1/4" from what I've read here on the forum. Might cause some vibration problems.
The '57-'59 Ford Car rear end is supposed to be the same length as the 8 3/4 rear. I've got one spotted at a junk yard but don't know if the pinion has the same offset as the Mopar.
Is the pinion on an 8" and 9" Ford offset like a Mopar? I read somewhere that the Mopar rear ends have a 1.5 offset to the passenger side from the centerline of the axle.