The first thing that you will find is that the upper ball joints are the wrong size. I changed the upper A arms on my early Dart to later A body and then installed '65 B body spindles and wildwood disk brakes (I had spare parts). I believe that if you get a pair of large balljoint upper A arms (they are available aftermarket) you should be able to use the F,M,J spindle setup. I say this because people do this spindle swap all the time on "B" and later "A" bodies.