Max, having re-read thru my old files of the Cadillac numbering system of the day it would seem that my memory wasn’t too far out, but it would appear that Cadillac engines were issued a seperate engine number upon manufacture (at the rear) and those destined for non Cadillac applications were not stamped at the front right of the block at all.This front numbering only happened when the recipient Cadillac vehicle was allocated that engine and that vehicles’ VIN was then stamped on the front of the block.The engine fitted into my J2X is a 1950 block and has the early EUN at front and back!This leaves you to uncover the rear stamping to id your number, and potentially you have the possibility that yours was always an original non-Cad fitment or, as I mentioned in my earlier posting, machined off during an earlier decking process to straighten the top of the block.
Roger
