Dating a fender bass
The first three digits refer to the manufacturer, CTS.
The last four are broken up into pairs, where the first two, 78, stand for 1978 and the last two stand for the week, which is the 18th.
Pickup Codes: OOWWYY Example: 202378 - It is believed the first two digits are an operator designation for the person operating the pickup winder, this according to Abigail Ybarra herself.
The second pair of digits are the week, but I have seen one example where the second digits were 72.
The first digit is supposed to reflect the year of manufacture, but there are major overlaps in this regard, and . An important thing to look for are the matching serial number stickers in the neck pocket and on the pickguard.
S7 5 digits = 1977-1978 S8 5 digits = 1977-1978 - I have seen a 1982 Strat with an S8 decal S9 5 digits = 1978-1982 E0 5 digits = 1979-1982 E1 5 digits = 1980-1982 Be especially careful with '79 Strats.
Some might go by the pot codes, but those could have been stock a year or more old by the time they were put into the newly finished guitar.
The '*' represents a middle digit that is either an 'X', a '-' or something that resembles a '1/2' or '1/4' fraction.
The trussrod was inserted through the back of the neck and the channel filled with the Walnut "skunk stripe".