As so often happens, these type of threads just peter out with no resolution. In the end I just didn't have the brass to offer them what I thought the machine was worth. After a few months of sitting there for sale the crawler was gone. Obviously I had no idea what happened to it.

Fast forward to last week. The widow of the big land owner in the area passed away in late winter, and the property was willed to several different people, none of whom I know. Last week as I was taking the kids to school I noticed a crawler tractor sitting there hooked to a chisel plow. On my return trip from dropping the kids off I did pull off to take a quick look, and it's most certainly the same D4E. I'd like to catch them sometime when someone is around in hopes of getting "the rest of the story". It doesn't make any practical sense for a big time operator to be chisel plowing with an 80hp crawler tractor.