When I was in the military we did some service on the APC tracks, changing pads mostly, and thus had the tracks standing on their side. When attempting to get them back down (they weigh about 500 kg) I used a one meter pipe for leverage.
Two other guys worked on each end with me in the middle but unfortunately they managed to tip it before I was ready, resulting in the pipe flipping up and hitting me on my right jaw.
I woke up about 30 minutes later in the ambulance. The tomography showed the brain was ok but a couple of my teeth were broken and I got a few sticthes. Couldn't read for almost a week without getting a serious headache though.
In retrospect, this was ten years ago, I think I got away in pretty good shape considering the forces involved...
Here is a vid of a similar APC, they are great fun but loooooots of maintenance.
YouTube - PBV 302 through the mudd
/b