Is your engine dis-assembled at all yet?
Are you sure the crank/pistons themselves are what is frozen, and not just some or all of the valves?
If not, remove the valve cover, and then remove the rocker-arm assembly... If the rocker-arms are not in place trying to move the valves as the crank moves, you may be able to turn the engine. I reccomend you remove the rocker arm assembly carefully so you can remember how to put it back together.
You may find that the crank turns so easily once the valves are not needing to move, that the engine may not be much a lost cause as you thought. Ken Crenweldge from this site saved me an unbelievable amount of work, by suggesting I soak my valves for a day or two in Marvel Mystery oil. Got my stuck valves completely unstuck and the engine runs great now. While waiting for them to soak and free up, I took off the rocker arm assembly to check how free the crank rotation was and make sure I didnt have any other problems, and without the valves opening and closing to create compression, the crank and pistons would spin easily, like a wheel. Several rotations on a single easy push.
Squirt Marvel Mystery Oil into the cylinders through the spark plug holes, as well as soaking the valves from the top. Some of the MMO will wick it's way up and help free the valves from the inside. But, it will also work on the rings/pistons to help free those up.
Unless you know that there is rust/corrosion inside the pistons and crankshaft/bearings, that old 235 might easily be coaxed back to life with some very simple treatments/fixes...
Since you've already removed the engine, though, all you may want to do is free it up enough to turn the flywheel.
Good luck either way.
Keith
