Mission accomplished! (Phase 1 anyway) I identified the problem, which is simply that the clutch facing is shattered:
http://edj.net/mc2012/1953clutch.jpgI made a scaffolding of boards so I could slide the trans back and away, without completely removing it. I should be able to slide it forward after fixing the clutch. Now the question is, how much of the clutch assembly can be saved? I noticed the little axle sleeve piece is broken. Do you guys think this part is available? Can the clutch simply be resurfaced? What do the stovebolt gurus say?
Only two dagnabits, a bloody knuckle, and three hours wrestling iron.