If you front mount it on an Ilex #3, it probably won't cover 8x10". Mine was mounted by S.K. Grimes (when he was still around) in an Ilex #3 in the conventional way, using the shutter's iris, and it does just cover 8x10".
The rear threads will cause vignetting, I suppose? I think Dan said he had done some surgery on his shutter to prevent that---if I get really excited about this project, maybe I'll get a dedicated front-mounting shutter and do the same thing, but I expect I'll use it more on 5x7 anyway, where it isn't *so* absurdly wide.
San Diego, CA, USA
The lady of the house has to be a pretty swell sort of person to put up with the annoyance of a photographer.
-The Little Technical Library, _Developing, Printing, And Enlarging_