I picked up an as-is GSN for $2 the other day. It had some issues like a bent filter ring, some mild lens fungus and a dented hot shoe. I fixed the fungus and filter ring damage (not too worried about the hot shoe) The only issue left is that the shutter is not opening all the way while firing. I disassembled the lens, cleaned the blades with Ronson and lubed the mech with oil. But I'm still having the same issues with the shutter not opening completely. In fact it seems that my cleaning and lubing had NO affect on the shutter. I can get them to open by putting pressure on the cams so I know its not an obstruction. I'm really out of ideas on this one. Can anybody give me any pointers?