Thanks. It looks like my post last night did not work right. So I was pouring water in the radiator and watching run right out on the ground. The coolant hose going in front of the oil filter had broken off the block. I am going to call the dealer today and see if they have that part that goes in the block. If it is a standard thread, I might try to make a temporary fix. I need to find an extractor to get that out of the block.
I searched the Messick site last night and could not find the part.
So apparently that hose piece broke off at some point and drained the radiator. Because I did not see steam or boiling water, the radiator was apparenlty drained at that point. The tractor seems fine now, but parked until I can get some coolant in it.