I feel like I'm involved in a kid's treasure hunt!

First, I stumbled on a Wollensak Verito in barrel, but luckily it came with a flange and was already mounted on 3.5" wood board. (The flange requires a 68mm hole in the board.)

I don't want to spend the money on mounting in a proper shutter (Ole told me it would have to be Ilex #5, I think), and the right Packard shutter would be way too big for my field camera.

Solution? I got a Speed Graphic with working focal plane shutter. It has enough bellows extension to focus it at a comfortable distance for portraits.

Only problem is, the Speed Graphic takes those little metal boards, and getting one drilled to the right opening size, and then figuring out how to attach a flange is project I'd rather leave for another day.

Option 2 is to try to attach that 3.5" board to the Speed Graphic. The board is a little smaller than the Speed Graphic's so there is a little wiggle; however, what's worse is that too thick to allow the metal locks to operate, so the board doesn't stay in place.

Any ideas on how to make the wooden board stay in place?