what year is my mustang 64 or 65?

[Frankenstang65]

One really easy way to check is by looking on the data plate on the driver's side door (assuming you can read it or it exists at all). The date consists of two numerical digits and and one letter. The two numbers stand for the day of the month that the car was built, the letter is for the name of the month it was built. If the letter on your tag is an A though an M, then your car is an early 65. Just to be sure, check to see if you have alternator or a generator, whether or not the outside front edges of the hood have a lip or not, and whether or not the windshield wiper posts stick up out of the cowl panel (the later 65s have a wiper that is almost flush with the cowl..the 64s have ones that are mounted a little higher up).

There are other subtle differences but this should be enough to be certain of what year you have.

Good Luck!