I am modeling a jig for a welding table.

The table is targeted to be 3/8" stainless plate with 5/8" holes in it, a 1.5" space, then a second identical plate.
I have some 2" thick blocks with 5/8" posts that pass through their corresponding holes on the top and bottom plate of the table.

I am trying to calculate the actual hole and post sizes I would really need to withstand my welder pushing against the blocks.

The attached image has a mockup of the scenario. I cannot find a bending/shear force calculation that matches my scenario online.

Any hints to point me in the best direction would be very helpful.