It was quite common for Fender guitars in the late 70's (and 80's) to have a sticker in the body with the serial number on, a good way to tell if the neck is original if the serials match. The large rectangular sticker on the bottom of the neck is still used today, and will contain the names of people who worked on that particular neck, maybe the guy that shaped it/put the decal on/tuners on/etc.. the various stamps on the neck/body are often factory codes.
Hope this helps.
Mark. :yikes