I have three 1972 gray bottoms all set to Fender recommended heights. I’m not sure what the 9400 on the middle one means. Could be coil turns maybe? Some custom job? Neck: Stamped 1842372 - Undetermined flying animal noises Middle: Hand Written 9400 - QOD Quack (duck) On Demand, based on attack Bridge: Stamped 1843272 -More of a soft Honk (goose) than a quack. Hope that helps. I think the real Quacks are responding to the thread. Honk, Honk. The photo shows the pups as they were when I traded an amp for the guitar in the late 70’s. .