Mark, the production summary by the Fox Collectors Association shows that one HE (Super Fox) was made with B frame engraving, and 22 were made with C engraving. The B and C engraving patterns are quite different. It isn't unusual to find HE's made without the "Not Guaranteed" stamp. Others that were originally stamped NG, had their NG stamp filed off or defaced by past owners due to misunderstanding on what it meant. If the HE you're posting about was made with engraved barrel wedges in addition to the frame engraving, that would be quite a rare configuration.
Please feel free to post on the Fox CA website while you are awaiting membership credentials. Our regular forums are open to all registered users. Frank Silvers
http://www.foxcollectors.com/ah_fox/content/he_fox.html 
