Has anyone created a Ground Glass focusing screen from a glass plate holder?

In concept this would be a repurposed non-museum quality glass plate holder with the septum partially (mostly) cut away and a ground glass inserted to replace the sensitized glass plate.

The idea is to make an effective , useful ground glass that can be used on any 4x5 camera that doesn't have a ground glass. This could bedue to a break in the field or to test/use a swap-meet or estate find.

The unit would be ruged enough, and convenient enough, to use in the field, as the dark slides would protect the glass.

What are the short comings or problems to anticipate or overcome? what are the focal plane registeration issues?

Anybody?