Ford Ranger rear end fit '71 Dart?
Something else to watch out for is the distance of the perch hole front to back. I never assume that the perch will center itself front to back. If the perches are identical from their front edge to the alignment hole, then you can measure from the edge to the housing. Used perches can set up off the housing different distances as well. If you set the perches on the springs then you can really eyeball everything with the rearend mocked up exactly where it will be. Might want to move the perches a little forward anyway to get that tire back away from the leading edge of the fender. But my drill press makes short work of new holes to align the housing farther back.