As you already know a typical rod may be repaired by grinding the cap down a few thousandths, torque it to the rod and resize. Why can't you grind both sides on the L32 rod and then resize. Has this been done? Will compression ratio change by enough to worry about it?

I guess it depends on how much you have to remove in the grinding process for it to be square, right? Removal of to much material will weaken the cap as well, i.e. the thickness at the bottom of the cap.