Mental note of importance:
Do NOT remove the two black screws beside the winding knob if you are just going to clean out the rangefinder mechanics.
The top is made of two covers, so the screws on the lower plate do not need to be touched (six around the outside and the two black ones).
… unless you want to curse and swear … an then spend the next hour trying to re-attach the winding spool.
When dealing with a dented circular metal piece that is threaded for a filter …
Get a wooden surface, a bamboo chopstick, and a light hammer.
Use the chopstick as a punch and lightly pound out the dented areas to form a circle again.