Boy, that's a toughie...
Without any experience in the art of 24 inch trunk dismantling, I would recommend that you tie the trunk off to several other objects so that it can't get away from you or fall where you don't want it.
Second, I wouldn't try to cut all the way through the trunk, but take pie shaped wedges out from various sides, and make the biggest wedge the second cut... so that you can control where it's going to lean. Then, adjust the rope that keeps it from falling that way, and lower it slowly to the ground.
It goes without saying that you do NOT allow any children around as you do this, and you certainly don't want a crowd.
Only those adults who are familiar with what you're trying to do should be present, so they don't get in the way, and so that they can follow your directions clearly at the right time.
how's that?