Long story short, an hour ago I was just given an almost like-new Mamiya 645 1000S from a friend that moved on to a few CM500s. I'm still giddy, as this is such a cool rig. I currently have a ProTL and a Pentax 67. This may very well replace my ProTL kit.

Everything seems to check out and it's supposed to work great. The battery check light stays on though after depressing the little red button. It's supposed to just stay on while depressig the button, just like every other check light in the world, right?

The switch feels a bit gummed up. Is there anything safe I could use to clean it without having the camera serviced?