Hi guys. You have it right. Bakelite was the name given to the original plastic for the knobs, pickup covers and trem arm tip. Bakelite was never used in the pick guards. The "Bakelite" of Fender lore is really polyethylene plastic. It was standard on all strats till late 56, when then began to switch to Polystyrene plastic.

This guitar has NO bakelite. If it did, the parts would be more rounded and worn, but retain a white brilliance. Bakelite did not yellow like polystyrene. You will see in this original, that the plastic parts have yellowed. Bakelite to this day, would be as white as a sheet of paper. Some 57's had all bakelite, but this is very rare. Most have none (like mine), or some. Typically, the pickup covers would be bakelite and the knobs polystyrene. A bakelite trem tip is very rare on a 57. I've never seen one, but hear they are out there.

This guitar is an example of pretty good condition polystyrene. It is a 5 57 body, so the bakelite was probably gone by then. For anyone interested, the potentiometer numbers 304 715 indicate: 304 means stackpole manufacturer, 7 is the year, and 15 means they were made in the 15th week of 1957, i.e., around early May. All the dates are reasonable on this guitar, 7 57 neck, 5 57 body, and May pots.

It is most common to see a later neck on an earlier body. For example, had the neck been a 58, the guitar would be considered a 58, despite the body. It is also quite common to see pots that are much older than the neck and body because Fender did a few large purchases. So sometimes the date range in the dating of a vintage is pretty large. This one is pretty tight, and all early to mid year.

Joe