According to Murray, Marlin didn't d&t the 336 for top mount scopes until 1960. Prior to 1960, the only factory d&t holes were the 2 on the left side of the receiver for Lyman/Redfield/Williams peep sights.
I have spoken to Doug a few times, when guns didn't line up with his book. He admitted that the book is a guide and not the final word, but it is, in general, a very good guide.
Jeff
