I am so confused. 

I am wanting to model C&O 14000-14990 boxcars. These were built by Pullman in 1945-1946. These cars had 10' IH and - 3-4 Improved Dreadnaught End with "rolling pin" main corrugations and lacking top narrow stiffener.

I have 6 of the C&BT cars painted for the C&O but these apparently are 10'6" IH cars. They do have the correct-ish ends other than they do have the top narrow stiffener. It was however suggested to me to use a different core kit and change out the ends.. So this brings me to my question. Are the Red Caboose "40' AAR Boxcars" the same as the "1937 AAR Boxcars" but with different ends or are their other differences? 
I have also read that the Intermountain cars were designed to use the same body but change the ends. I would consider these, but I don't know if kits of these were ever produced or just RTR. 

Does anyone make a 10 IH 3-4 Improved Dreadnaught End with "rolling pin" main corrugations and lacking top narrow stiffener. It was suggested to me to look at Yarmouth Models but I don't see them on his website. 

This then brings up the question I asked last week, Where do you draw the line? Yes the C&BT cars are too tall, but on a layout, would you ever notice that? Same goes for the slightly different ends.