Mystery E&HT Anthony View Camera - Almost 8x10

[Icecreamguy]

Hi all - long time lurker and first-time poster. I'd love to hear anyone's thoughts on what this might be, if anyone's so inclined to offer very-appreciated support. A friend gave me an ancestor's beautiful, very well-cared for view camera. It appears to be an E&HT Anthony Clifton 8x10. Except it's not exactly 8x10 - the ground glass measures 7 3/4 x 9 5/8 inches. I cannot find information on a Clifton model this large - the Clifton long focus came in 8x10, however this one lacks any rail extension, so I don't think it's the long-focus model. It just barely doesn't fit an 8x10 holder - like it's not just a matter of a tight fit, it truly does not fit an 8x10 holder by about an 8th of an inch. I'm curious if this may have been manufactured with some kind of off-size E&HT Anthony holder that fit 8x10 sheet film/plates, or if it was some other historic size that I'm just not able to find any information about. If it is some kind of custom Anthony holder size, does anyone have any suggestions on where I might obtain one, or have one made? I make my own lens boards out of matboard, but film holders are far beyond my capabilities. Any info or advice would be greatly appreciated!

Julius