Although the information is hard to find, there is a Cummins 6. 7L B Series engine available for the Ag market. It appears from the bore & stroke callouts that only the stroke is increased. I wonder if you could purchase the crankshaft and connecting rods from Cummins (provided we had the part numbers) and bolt it up? It may require modifications to the engine/oil pan, but wow, how unique would that be? Cummins 6. 7L Diesel!!