If you look at the first
If you look at the first Mustang, it was officially a 19641/2 model, which could be classed as a 65, but it really wasn't. I don't know about you but I saw it for myself. And, another comment, the first Mustang was not looked on as part of motorsports. It was billed -- and I kid you not -- as a secretary's car. The small engine and real lack of any sort of big engine left it in its original category.