Thanks... I got it out with the "oven" process. But there's a surprise.... The crankcase I want to use is from a "parts" engine, and I want to use it because it has the factory holes drilled for a bolt-on muffler. But the two parts are not identical on the inside. The one with the "muffler holes" has a good size groove machined in the bottom of the crankcase, in line with the rotation of the connecting rod, apparently to give the con-rod some clearance. The other case does not. Could this be a long-stroke vs short-stroke issue? I'm thinking I might be better off having a machine shop drill and tap holes in the "new" case that doesn't have muffler holes, using the "parts engine" crankcase for location,depth, and tap thread details... thus avoiding any part swapping. What do you think?

ChiefK