Quote Originally Posted by sangetsu View Post
The washer shown does resemble the washer used between the shutter and the front standard, but the aperture assembly would not work properly and the shutter assembly would be loose if the washer were ommitted.
There is also another washer behind the lens board, between the lens board and the shutter retaining ring/light baffle piece. This is where I think the washer came from. It being left out won't affect any mechanical systems.