From the front bow to the back of the door they should be the same on all closed car bodies. From there back is anybody's guess but you can always modify a long one. 41-48 may not be identical but may be usable anyway.
I thought the '40 two-door cars would be the same, but didn't know how close the other years would be. I would think the later years' cars might be a bit wider, which would allow for some modifying. It appears all the bows aft of the doors are the same length, judging by the one bow I have. Thanks for the input.