But... you can call me Meli...
This is another good question that is often asked about old tractors of ALL kinds!
We have a 1950 or 51 B. Do you have any good ideas of how to unstuck the engine?
Sometimes you can get the engine free by filling the cylinders with a mixture of kerosene and automatic transmission fluid, or fill them with WD40 or "Liquid Wrench", "Marvel Mystery Oil", "Gibbs", or any other penetrating oil. Let that stuff stay in the engine for days or even WEEKS! Then bolt a long bar to the flywheel and see if it will break free.
HOWEVER... Even if you get the engine loose this way, you STILL need to take it apart!! The rings will probably be stuck in the pistons and they won't seal. The valves will probably have "crud" on their seats and they won't seal either.
THEN..... There is always the possibility that the reason the engine is stuck is that at one point it came to a screeching halt when something BROKE inside of it!! In THAT case you HAVE to take it apart!
Good luck, Mike!