Jtplumb said "I don't think there were more than 1200 of these crossbolt guns made, tuff to find any good info."

The best current information source is the Lefever Arms Collectors Association web site.
URL is: https://www.lefevercollectors.com/

You have to register in your own name to reach the web site and the Newsletter Archive is restricted to LACA members, but the majority of the information is then available to you. There are good images of all grades of both the side plate and the crossbolt guns.