Leaf spring centering pin diameter?

I got a new set of leaf springs with no centering pin. What is the most common diameter of the centering pin for the XJ applications? When I went to order a pair, there were sizes of 5/16", 3/8", and 7/16". Thanks.

Measure the holes in the leafs. You're far better off grinding the holes in the perches out a little than you are expanding the holes in the leafs.

EDIT: Also, I am marveling at how many of the threads in the "related threads" box at the bottom of the page have almost the same name.