Anybody have a good idea of how to get stuck pistons out of an engine? Got AC wd-45 tractor, stuck motor, the two middle pistons are almost straight down, but lack a bit. got the front and back ones loose but center ones won't budge! soaking for a week, still no go!

Assuming the crank is out and the head is off, a chunk of 2x and a lump hammer. If the crank is still in, maybe try rocking either the fly wheel, or the whole tractor in gear? If you have a junk starter, you might want to take a page from KOO:

https://www.kingofobsolete.ca/KING%27S_BAR_STARTER_WEBPAGE.html

Tried it in gear, no go, --it's got the 2 middle pistons stuck bad!---motor still in tractor, so not sure of the next step. May have to take the motor out, gotta put new rings in it, lots of carbon in the head and on top of pistons.