Crankshafts with badly worn journals or spun bearings can have material welded onto the journals and reground back to the proper diameter. That requires a total engine teardown, so if that has been done the whole engine has been disassembled and rebuilt. I would have tried to find the head gasket leak by either putting air pressure into the cylinders one at a time to figure out where to start looking for a problem, or bypassing the radiator with a couple of hoses and attaching a garden hose to the cooling system. With the spark plugs removed and a few pounds of pressure applied, water will squirt out of one of the plug holes, showing the general location of the leak. If you're getting water out of the exhaust, it's possible there's a crack in the head that goes into an exhaust passage. That can also be found by pressurizing the engine, but the intake and exhaust manifolds have to be removed.
Jerry
