Date Codes

A Number Signifying the date precedes the month code letter. Second
year code letter will be used if 1963 model exceeds 12 months.

MONTH                 CODE 1ST YEAR        CODE 2ND YEAR        
January               A                    N
February              B                    P
March                 C                    Q
April                 D                    R
May                   E                    S
June                  F                    T
July                  G                    U
August                H                    V
September             J                    W
October               K                    X
November              L                    Y
December              M                    Z