Many years ago i had a Massy Ferguson 178, we could not get the head off for a engine rebuild so me and the fitter removed the sump and i am sure the pistons came out the bottom and he shoved bit of 2x2 up number one bore and one up number four and jacked the head of with two trolly jacks, one under each bit off wood.
This was over twenty years ago but i am sure it worked.
We were warned by a older guy in the workshop to watch our eyes if we cranked it over as diesel squirting out between the head and block could blined you