This may be of interest. I have modified a broken Olympus 50mm lens to use the helicoid as a focusing mount for a Super Angulon 65mm lens.

Some info here:

http://www.apug.org/forums/forum147/64210-temporary-6x6-wide-angle-camera.html

http://www.apug.org/forums/forum147/62515-wa-6x9-folder-my-pocket-5.html