success! not sure exactly what i did other than to dismount the lens board and reset back in the body. i would check the focusing mechanism back and forth without the board screwed in and camera laying on its back. initially, i would see the lens board rise as i moved the focusing knob to infinity. i reset it a few times (taking it off, sliding it back on) and on one of those occasions, when i moved the focusing knob, the lens board did not rise. i then attached the screws, checked the focusing knob again and it moves smoothly to infinity. now to try to figure out why the shutter ring is so tight!