Freeing up a frozen block ??

A third vote here for the Marvel Mystery Oil.
Pull the spark plugs out and load a bunch in the cylinders, put the plugs back in, and wait a few days.
Diesel fuel works pretty good too.
We used to call it giving the engine a diesel fuel enema...lol
It helps if you take the rockers off so that you aren't trying to move the valves too while you are trying to turn the crank because they are probably stuck in the guides.
After you get the engine to turn over, to get the valves to move, sometimes just a firm hit with a dead blow hammer to the top of the retainers will free them up.
If not, then use MMO and or heat will loosen them up.
Patience is a virtue here...