When you say it is a 65, do you say that because your title says 65, the PO told you it was a 65, or because the serial number says it is
a 65? You serial number should be J O(I) 26 5 XXX or S O(I) 26 5 XXX to be a 65. If it is a 66 the serial number will be J O(I) 26 6 XXX or S O(I) 26 6 XXX. 1965
is very close to the 1966
introduction of the Corning chemically tempered windows. There is a very good chance yours was one of them. It is very common for odd balls to slip out of the factory. It is also very common to see a sudden and abrupt change in the production coming from the factory. The new years model usually came out around October, sometimes it came out earlier.