Nate, based on the styles you listed, it would actually be (at least) four different styles. The "common" longer style would be for dual exhaust cars. In actuality, the true common style would be the single exhaust style which was different (unless I'm misunderstanding how you referenced the "longer" one).
Just for reference sake, I would be curious to know if the dual exhaust style tie down changed between the 64 1/4 cars and the 65/66 cars.