I just looked at a Super M in perfect original condition. I mean down to the original fabric on the seat cushion (whats left of it anyway). No dents at all, no rust, original paint. The problem is there is a hole in the rear housing up under the center between where the two axle housings bolt on. You can see where one of the big gears (bull gear possibly) came through the case. What do you think caused this? And do you think my guess of $600 for a parts tractor and $600 labor for a total of $1200 would fix the problem. Any recomendations on what happend and what it would cost to fix it would be appreciated.