Did the various cots that were used through the years all use the same cot bars, or were there specific cot bars for specific cots? The factory picture of my 1963 Pinner shows a long cot bar, but when you try to hook a cot to the long bar, the cot has to move too far forward, and then you can't use the jump seat. Since the factory photo doesn't show a cot, then I am beginning to think that they just installed any cot bar that they had, and let the customer buy the cot after delivery. thanks