I've done some major mods to make the model correct for 7513. As it comes it's not correct for much of anything. I have a very long list on the Atlas forum if you'd like to see all I'm doing/done. One of the more obvious things is raze the roof. UP 7500-7509 came with the engine compartment doors even with the top. 7510 and on, there was a 8" space from the doors to the top. There's a long list of things, take a look.                 

Thanks, Bobby Pitts

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