I managed to score a M-39 mounting flange for the lens board. I have a choice, take the board to a machine shop and widen the opening by a milimeter so the flange sits flush. My other other option is mount it upside down and just mount with some self tapping screws. Then the lens would sit a couple of milimeters off the board if that makes sense. That would save auditioning of a machine shop.
I liken my new De Vere to owning a really cool early 80's Aston Martin Vantage.