Dating fender guitar pots
They are believed to just be some kind of quality check stamps.
Pot Codes: MMMYYWW Example: 1377818 - In 1977 found on the side of the pots, moved to the bottom (and unfortunately sometimes covered with solder) in 1978.
In 1979 a notch was added for a ground wire lug in the control cavity and output jack cavity and a black shielding paint was sprayed into the cavities right over the lugs and wires that were soldered to them.
Necks are Maple, and are constructed from one complete piece if they have a Maple fingerboard.
Be aware of another code found on these pots, 013446.
It has nothing to do with the date as I've seen the exact same code of pots ranging from 1977 - 1981 strats.
The trussrod was inserted through the back of the neck and the channel filled with the Walnut "skunk stripe".
This manufacturing process was used regardless of whether it was a Maple or Rosewood fingerboard.