Can a veiwing hood from a spring back be installed on a Graflex back?

Wellllll. it depends. I just tried it out on a 2x3 mini to mini and yes with some minor work with a table saw, it would work.

Now I've always held to the common belief that graflex holders were wider than graphic holders. Maybe that's true for 4x5 and larger. If so you'd have to make "adjustments" .

You'd also have to check to make sure the ground glass is in the same plane of focus as the film.