What's the problem with mounting it? Won't go through the lens throat?

If that's it, one solution is to mount the monster in a cup-shaped adapter that attaches to the board. I believe this is essentially what the JoLo mounts for 7"/2.5 Aero Ektars are.

I have 2x3 Graphics, whose boards are tiny (2.5" x 2.5"), and have had the same problem with fat lenses. Skgrimes has made several cup shaped adapters for me to hold my fat lenses (100/2.5 Uran-27, 100/5.6 S.F.O.M., 4"/2.0 TTH, 12"/4 TTH telephoto) entirely in front of the lens board. You can read about them at http://www.galerie-photo.com/telecha...2011-03-29.pdf As you'll see, there's more than one way to attach the adapter to the board.