Was told my SS is a 1965, but from what I can make out in 65 the serial numbers were found on the headtube? Mine are on the left side rear drop? K5118. Anyone have any info while I try to look it up? Heres what Sheldon Brown had to say about it. (RIP)
Before 1965 serial numbers were stamped onto a rear dropout. Beginning in 1965 serial numbers were moved to the head tube and the following date system was used for all Schwinns except Paramounts. The letter at the beginning of the serial number indicates the month of manufacture, skipping the letter "I." For example, "A" = January, "B" = February, and "J" = September. The second letter of the serial number indicates the year of manufacture (not the model year), beginning with "A" = 1965. Skip the letter I & O. Sports Tourer KH017873, for example, was built in October 1972."