Collin, I have an article on MX shutter lever adjustments at:
http://ca.geocities.com/spirope/mxmlu.htm
Tiny alterations in the angle at which the actuating rod is set can greatly alter the behaviour of the camera. You can get mirror lockup by having the mirror lock-up by pressing slowly and gently on the shutter release (instead of flicking), or you can have the mirror not go up at all! It's a relatively easy adjustment to do (it must be, as it's one of the repairs I managed to do without messing up the camera.)
