Width between spring perches on a MJ?

[1989 comanche mj]

I am getting ready to swap a explorer rear into my 92 Comanche, changed to 456 gears and put new seals and bearings in there.  Problem is, my truck had a spring over conversion at some point in the past, and I see the remnants of the original bottom mounts and they don't match up to what they welded on top!  One looks a little to the left, one to the right, I think it was all eye balled.

 

Can someone tell me the leaf spring center pin hole to pin hole width so I can get the new one in there square?  I know its tough to measure with the diff in the way in the middle.

[Strokermjcomanche]

42 inches center to center