[Fordors]

SAJ, do you suppose it would help if someone had a main leaf that they were sure was original and they measured it? Not for arch and C-C of the eyes, but using a tape measure along the top surface give a C-C dimension.
This would eliminate one variable would it not? Another thing to consider, one can set the arch and have a good C-C, but even then, if the spring rate is too low in effect the car could sit a bit low and the shackles would be affected as yours are.