I would avoid the Crown Vic as it will fail when cyclic metal fatigue catches up to the magic number. Flexing ladder frames and aluminum do not mix. It is just a matter of when not if.

The new 65 66 Dakota kit from Steve may fit a later 67 F100 it would have to be scoped out on a frame. The F250 frames are about 1 inch taller.

If you want a 8.8 IRS with a locker with disc brakes i have one in the back yard.

Garbz