1974 Dart Swinger - resto/fix-up/hop-up
re the rear end, it's common to swap in a ford explorer 8.8. they come with (mostly) 3.73 gears, lsd, 31 spline axle shafts and disc brakes. remove the 'long' side axle and cut the casing down 2 7/8", then fit a second 'short' side axle. this gives the total width almost exactly 'A' body size. parts are much cheaper than a mopar 8 3/4 due to the popularity of the 8.8 in mustangs.
neil.
ps lots on here about this swap if you look.