When i bought my 69 vert in January. i said to my wife...Man that's a long car. I guess it's because of the vert. top needs space to drop down behind the sea. The back eand of the car is long. My wife's 73 E body is short in the back.
It is no longer than a fastback or notch. Convertibles just look longer with the top down. The space for the top was made up with a slightly shallower back seat.