Found one more picture that shows the numbers stamped into the ring gear at a slightly different angle. The number looks like it might be a Chrysler factory part number for a 3.23 gear set.
I will go back over and look inside the splined axle bores to see if there are any buttons in there. I'm now thinking it's possible metal particles might still be on the gear teeth and causing the erratic back lash readings we saw so we will check that again.
Also, would it be practical to start looking for a couple sets of OEM Chrysler wheel bearing kits to go back to tapered roller bearings with an adjusting nut in the RS retainer plate? And, is there anything else I should get a picture of and post while I am over there tomorrow?