Both the shutter and mirror stay up. The frames are 'lost' due to overexposure.

I've sent an email to Eric Hendrickson who told me to clean the release selenoid. I'd like to open up the camera myself - the quandary has become irritating and I feel like a helpless housewife with a broken hoover. If anyone could advise about taking the 67 apart and, since I'm expecting a whole universe of mechanisms in there, where exactly the selenoid is?