While there have been periods where dramatic changes have occurred, for example: the transition periods between Leo's Fender and the CBS years, as well as the transition between CBS' Fender and the current ownership, generally speaking, most models are feature specific and do not change from year to year.
On the heel of the neck should be a penciled or stamped date with a month and year that it was assembled in.
Other areas that contain Serial Numbers are on the top of the Neck Plate and the front or back of the Head Stock.
Though it’s not the first electric solidbody, the Telecaster is without doubt the first commercial electric guitar manufactured in large quantities.
The Tele is an American icon and is well know for it bright tone.
The color was originally a two color sunburst pattern, although custom color guitars were produced.
Nobody could have foreseen then how the Stratocaster would go on to revolutionize popular music.
So, obviously a neck date, while being helpful in providing a date range of production, it cannot be a definitive reference.
Unlike the auto industry which has specific model years for their products, most specifications for a given Fender instrument model, change little if any, through the lifetime of the model.
Over the years Fender used modular production techniques that may have resulted in a guitar that has parts from one year to another.
Parts may have been produced in one year and left in a bin until they were ready to be paired with a body.
On some of the early Stratocaster’s it was stamped on the back of the Vibrato Cover Plate.