@Dan the man "I wouldn't own a A body before 1968. "
There isn't as much room for big wedges and such but many have swapped those in and a strong small block or a stroker can be a force to be reckoned with. (Thanks to Ed and Scott)
I could have gotten a 1966 dart but it needed a complete front clip and I wasn't having much luck in finding it so I don't it would be better if I stayed with a car that has replacement body parts available for it.