If your going to be using a old OEM Dana 60 out of a original Mopar production car body the right side axle tube and axle will be noticeably shorter on the passenger side than the drivers side, this was done to center the pinion yoke in the center of the tranny tunnel that is offset in all Mopar production cars from 1962 and up until they quit making rear wheel drives cars that I know of
See my first comment on your results