I tried that VIN decoder and it is definetly incorrect. I put in the VIN for a 1960 2 door sedan and it says its an Impala SS. We all know that there were no SS in 1960.
If you look in your book your will see that the 61,62,and 63 Model number listings do not show any SS listings. See pages 21-23 but on page 24 it shows the 1964 Impala SS model numbers 1347,1367,1447,1467.
The seperate model numbers for SS went through 1967. That is why these year cars are harder to fake, you have to commit a fraud to make a fake SS in those years.
That goes for US cars Jason. I can't comment on those north of the border!
Hope you are having a good winter up there.