Info on old serial numbers is sketchy at best
On pre Ebonite>Columbia balls the first digit typically indicates year.
If The first number in the serial number is a 6. That denotes the fact that it was produced in a year that ended with the number 6, as in 1976, 1986, 1996,........
Number is the year, letter is the month produced! N started the year -no O - P Feb and so on!
