A friend of mine just put a C-15 6nz engine in older frieghtliner tractor. He used a wiring harness from mawk industries. Looks to be a pretty well laid out harness. They make them for cat, cummins, detroit and i think international. Thier web address is www.mawkindustries.com. They might be worth looking into if anyone is thinking of doing a late model engine swap. Does anyone know of anyone else selling harnesses to do these kind of swaps?