Help with an old cast iron furnace

Did a load of searching on the forum for this, couldn't find an answer, so here goes.

So my grandpa, who is 70 something, had to get a new heating system put in his house. He knows I scrap to make some extra money, so he told the guys they could leave the scrap in the basement no problem, and I'd pick it up. Thing is, they took all the good stuff, and left all the crap that is worthless. It's been sitting down there for a few months before he even said anything to me. I just found out about it over the weekend, and figured it's probably too late to call these guys up to get them to haul it out. I just wanna get it done for him now. It can't come out in one piece. Stairs are busted and made of plywood, and the stairway is now too small to take it out in one piece as well. So i've been going at it all day taking it apart. Got most of the stuff off, now I'm just trying to separate the cast iron chunks but.... it's not coming along smoothly. any tips? I'm thinking I may just need to go out and buy one of those huge iron chisels to help break it down. Was using a small old beat up chisel I had laying around, and it's dull, and split in half on me.


So here is where I started on the right trying to knock the first section out. at the bottom is where I took out my grinder seeing if I could get it to separate easier, but I was kicking up so much dust, and I left my respirator at home (not thinking....)





view from the top. It's starting to separate on the left, but I don't know if something is still holding it together, or if I'm overthinking it, and need to muscle it.






Only thing I can think of: is this pipe on the right holding this thing together still, as in, is it going all the way through? I don't know why it would be, but I tried getting it out, but it's also not budging, and I don't know a good way to get it off. Tried multiple wrenches and lubricants. It's stuck in there pretty good.