Hi Jon,
Great stuff! That tune reminds me of 'Old Joe Clark' but it might be partly because of the style of playing. So 1838 in a play in Nashville it is 'Tail'd' rather than 'Tail'. Pity we don't have that text yet.

Couple of points about that 1846 Yazoo text. It has the look of a new version and 'Jim Crack Corn' all has capitals implying possibly that it's a one-off pseudonym/nick-name like 'Jim Crow'. Also the lack of 'and I' presents the same possibility. Further it adds sense, saying this Jim Crack Corn didn't care about what happened to his master.