Have you confirmed this (just asking since I haven't) to see if the date on the label is the real production month or if it's like the door tags of the earlier years where it lists the projected build date?
Would take a while cross referencing a bunch of marti reports and door labels but could be done - just access and time
I have not cross referenced multiple VCL's, but my 11/19/69 scheduled date Cougar that was actually built 12/01/70 has the manufactuered date of 12/69 on it.
Also the language on the label states,
12/69 This vehicle conforms to all applicable federal motor vehicle safety standards in effect on date of manufacture shown above.
I have been wrong before but that is what I currently believe based on the small sample size that I have.