These have a letter prefix starting with “A” followed by only 5 numeric digits.
The serial numbers were stamped on the bottom of the foot at first but between SN A66544 and SN A74901 it was moved to the Housing.
I cannot tell you where this originates, except that at one time, it was free information on the Mitchell Reel Museum."Dating a Mitchell reel is easy if you have the right tools and here it is; the original Mitchell Fishing Reel Dating Guide! ARMYSHOP 008 ARMYSHOP OUTDOOR Bohemia Air Soft D-S-T-I EXCUBITOR - Cop Gun Center Jare Roman Kentaur Zbran Koen vrobky ECHO Krav Maga IKMF CZ LHS Holsters Libovick Radek Leiko LOS - Lidov obrann stelba POLICE-SHOP AKAL shop SHIELD TECH s.r.o. I am not an expert or all that knowledgable on anything discussed here. My saltwater has been inside inlets or just a little out.Other Classic Egg-Shape models made after 1970 were included in the same serial number sequence.