If that is the one I'm thinking of (and I think it is), I wouldn't really call that a partial ejection (at least in the way I think of the term).....he ejected into the ground when the jet rolled/departed at 600' AGL. So well outside of the envelope unfortunately.
IIRC, I read that the ejection seat was 1/3 of the way out of the cockpit. Not the case? From seeing it from the tower (I was on Ground that evening), he never ejected.