Got this photo of a Cletrac beside a D10 from the June-July 2006 edition of Engineers & Engines magazine...  apparently it's owned by Carl Mehmke and the article lists it as a L Cletrac  looking at your website it seems to be a model F  ... ???

This picture clearly shows how Caterpillar took their idea of a high sprocket from the model F Cletrac which used a high sprocket some 70 years earlier. (editor)