I recently bought a Rolleiflex 3.5E, version 1, with 75mm 5-element Planar. i've tried two Bay 2 lens shades, but they're too big. I read somewhere that the mount on the early 3.5E's is smaller than the 3.5F's, or later 3.5E's. Any idea what I should be looking for? Will Bay 1 work?