Someone help me Date these Fender bass pickups

[copperheadroads]

Got these in for repair
with one dead coil & the 4 digit serial number kind of confuses me . looks like 0451 to me .
Grey flatwork , Stamped number , Pvc wires , Looks like Formvar wire

[big_teee]

I'm guessing here, but could it be?
May 4th 1971 ?
T

[ken]

Are the coils lacquer potted or waxed?

They look like 1971 pickups to me

Ken

[copperheadroads]

Lacquer potted & the color of the wire looks like heavy Formvar but it's just single coated 42 gauge wire ,machine wound .

[Lyrebird Steve]

From what I've read up it seems the most convincing description of the serial stamps for Fender Pickups is as follows

Pre-1974 had 4 digit stamps X YY Z where X is batch number, YY is week number, Z is last digit of year ie 197z

1974-onwards had 6 digit AB YY ZZ where A is line (?) and B is Batch (?), YY is week, ZZ last 2 digits of the year 19zz


So yours read initial batch made between November 8 to November 14 in 1971

Hope this helps