"F" style tuning gears replaces "Kluson-Deluxe" gears.
At the Fender factory they used old tube charts when new models came, probably because the tube layout was the same.
Determining production date by serial number and transformer codes is better, and you should also inspect the circuit to be completly sure.
Production years 1964 -1967 “blackface” circuits AA864, AA165, AB165 1967 -1977 “silverface” circuits AA165, AB165, AA270, AA371, AA568, AC568, AA864 Tube layout AA864 Tube layout (Seen from behind, V1 is to the right side): V1 12ax7 = Preamp bass channel V2 12ax7 = 2’nd gain stage bass channel (and normal channel for AB165) V3 12ax7 = Preamp normal channel V4 12at7 = Phase inverter V5 6L6 = Power tube #1 V6 6L6 = Power tube #2 Summary The Fender Bassman is a legendary guitar amp known to both guitar and bass players.
It was introduced in 1951, primarily targeted for bass guitar players and promoted as a bass amp for the Fender Precision Bass guitar, the first mass-produced electric bass guitar ever.
Also a thin aluminum shield the size of the pickguard is installed underneath the pickguard.1961 Stratocaster : Peghead decal logo now has 2 patent numbers (2,573,254 & 2,741,146) 1962 Stratocaster : Peghead decal logo now has 3 patent numbers (2,960,900 added) Mid 1962 Stratocaster : Veneer Rosewood fingerboard.
Bottom of fingerboard (part glued to maple) is arched. This transitions in with the smaller side dots becoming pearl after the larger 1/4" top dots become pearl.A small aluminum shielding plate is installed underneath the pickguard that covers the control cavity. Also available without tremolo (known as a "hardtail" model). 1958 Stratocaster : Sunburst finish changed to three colors (red added).1959-1964 style Stratocaster Mid 1959 Statocaster : Slab Rosewood fingerboard with white "clay" position dots."Small" peghead, round string tree, truss rod adjusts at butt. Serial number on neck plate (except April to May 1954 models on back tremolo plate).Neck is 1 piece of maple with black dot position markers.These two guys along with the Blues Junior are the mainstays of Fenders current tube army.