Thanks for the replies, but I am afraid I don't completely understand the answer. First, what is a crash box? Just a standard gear drive? Or is the SOS included in that generalization? It is nice to know there are options out there that will also work well, especially the bit about the Sherman.
To give a little background of what I would like from the tractor - the tractor would immediately be completely disassembled and everything gone through. Once complete, it will be expected to work, but only to keep it exercised. I have about 3.5 acres to till where it would share responsibilities with a 1950 Allis Chalmers WD. I also have a Kubota BX that works around the house, but it would be nice to add a hydraulic pump and loader to an old diesel ford for some jobs out in the woods. I would expect that 70% of the 801s responsibilities would be to look good for shows.
The tractor that caught my eye is an 801 with a diesel engine, SOS transmission, and 4 wheel drive. I thought it would be a cool tractor to keep around. This would my first complete rebuild and was thinking it would cost about $5k to do it for the most part on my own - is this a reasonable assumption.
Thanks