[QUOTE=Sierra]
Prior to 1970, the serial number format was MYxx, where M is month indicator, Y is year indicator and xx is sequence number.
Thanks for that info. Didn't realize that. I've seen that scheme on the early Schwinn Super Sports and Superiors with the forged Huret rear dropouts, but haven't run across it on the Paramounts(I don't see many early Paramounts!).
While MYxx was the previous format , it was short lived (on Parmounts it was in use from only 1966 to 1969). The short life span undoubtedly contributes to the scarcity of samples.