Pushrod oiling/heat?

Well no, most times, the shims need to be thicker on one side to allow relocation of the rocker shaft in order to get the correct rocker sweep on the valve tip correcting for the poor Chrysler valve train geometry. That SHOULD BE the only reason for placing any shim under the rocker shaft.
I wasn't trying to address the geometry correction or the math associated with it. I'll leave that to Mike. Simply pointing out how to make the shims. If they need to have an offset, that adds a little bit of complication and maybe is easiest to accomplish in the mill.