Go for it! Like Rick said, both bodies are valuable, and even though the recently discovered C&S?RGS box has an identical roof, no reason not to have two of them surviving! The Boulder group has done a great job so far, and I think we all know that you have done a lot by buying up cars already.
Plus, like you said, there is just too little left of the C&S to ignore ANY carbody. So much has been lost from that line since abandonment, it just breaks my heart to think about it.
Good luck!