Actually, '64 1/2. I had one. Mine had a 260 V-8 motor. The 1965 optional V-8 was a 289, which was a 260 block btw.
"Actually, '64 1/2."
You're right, that's when the production year for that model Mustang started. However, they were designated as '65s. See my post # 89 for links to Ford's Heritage website & their official statement to that effect.
BTW, I had a '67 Candy Apple Red Mustang - my 1st brand new car. Wish I still had it now, LOL.