I lent a 12" Commerical Ektar to a friend of mine and while that was happening, I got me a 4x5 Cambo SC. So while I'm waiting for that come back, here's a question. I'd like to mount the 12" on to the Cambo and from what I read, my 21" monorail can accommodate the focal length. Does anyone know what size Cambo lensboard I need? Its a 12" Ektar with an Ilex shutter. Would I be able to get any inexpensive used Cambo lensboard and have it drilled out or is the lens to big for those? Or is there a Copal # size that I need?