I'm interested in obtaining a Nikkormat camera, and today I went to look at one that is advertised locally by a private party. The camera appears to be in very good condition with working meter, etc. The only apparent problem is that the indexing pin would not rotate past about the 10 o'clock position. This means that the pin cannot be engaged into the fork on the lens. The lens can be mounted without engaging the pin in the fork, but there's no indexing to the camera body and stop-down metering must be used. It appears that there is some kind of interference between the indexing ring and something located behind the Nikkormat nameplate that's preventing the ring from rotating. Does anyone have an idea what the problem might be?