I searched through the Tech-Tip linked above and could not find the word "serial", or the term "serial number"" in it.
That's technically correct Tim but the techtip says (referring to the serial number on the body plate) "The number on the plate is the Vehicle Identification Number (VIN) of the truck." which isn't necessarily so. Yes it's the unit serial number but depending on the state it's probably not the VIN. My other point is that while the acronym V I N wasn't used then, whatever number was used to identify the vehicle it is in essence the
Vehicle
Identification
Number.