Never lettered it, but this Pre-17 4 screw shipped in October 1957 making it a fairly late shipped pre model.
I posted in the lounge about me and my Dad going shooting together for the first time in over 30 years, and this gun saw a lot of action that day.
It is up for speculation whether it shipped with the ramp front sight but it definitely looks factory.
Very nice Curtis and good memories as well. I have a K-32 from that year in the same configuration. Looks original. Maybe the factory was generating a few at that time.