Mustang II suspension conversions need frame rails that are relatively straight (at the mounting point), the right distance apart and and at the right height. Shoe box Fords kick up and out. The only craftsman like solution is a stub frame.

My friend Roger Cope s building a 46 Olds for a customer. The frame simply will not accomodate a Mustang II suspension. So he is having the stock lever arm shocks rebuilt (the are also the top "A" arm) and the spindles modified for disc brakes.