There use to be a cast iron welding shop in Concord, CA according to one of the local machine shop owners. Exceslweld or something similar in name. He says they closed up but any heavy duty Diesel repair shop should know of a good cast iron welding shop I've had heads worst than that repaired years ago by another H.D. dieselrepair shop in SO CA named Cyclone Excessweld so maybe there is a chain of Excesweld shops still They do grind the crap out of the head where the cracks are to get rid of the bad material and then weld them back up and rough machine them for you as part of the repair, I was told that they preheat the part in a oven for 24 hrs and then do a little bit of welding at a time until the repair is done and then take 24 more hours to let it cool down Good luck, let us know what you do and how it works out