Given the modular nature of Fender's production techniques, an individual neck may have been produced in a given year, placed in the manufacturing warehouse and remained in stock for a period of time, and then subsequently paired with a body to create a complete guitar in the following year.So, obviously a neck date, while being helpful in providing a date range of production, it cannot be a definitive reference.To read this it is necessary to unscrew the neck from the body. Most notably, production dates have been penciled or stamped on the butt end of the heel of the neck of most guitars and basses.Some dealers simply go by the serial number, which you will discover can be far from accurate.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.At the top of the neck plate, at the front or at the back of the head or on the cover plate of the vibrato.(Stratocaster) Between 19 there were periods that this is not consistently done.
So, you can't afford that '54 Strat, or that '64, or even that '74 for that matter.
While there have been periods of dramatic change—such as the transition periods between the Leo Fender years and the CBS years or the transition between the CBS years and the current ownership—most models are generally feature-specific and do not change from year to year.