Ian, the KDC on the base of the cylinder may mean Komatsu Dresser Company, which was a joint venture between Komatsu and Dresser, intended to supply very large mining haulers. If so, I don't have any idea why it would be on this product.
Briggs and Komatsu got together on this engine. Theres a whole story about it on Wikipedia.
I would say that these engines were made in a KDC factory.
