And when you're done finding John's rear element (hmmm, don't read that too closely without viewing the rest of the thread), you could visit me and help me find the 4 adapters I've misplaced that would let me put 3x4 film in my 9x12 plate holders. I've got film sheaths, I've got film, and I've got plate holders -- and now I can't spot the adapters... :P