Just keep working from the top back towards the stump. When the tree gets a little bounce to it, it's going to try to stand up if you take much more weight off. At that point, go back to where the home owner made the original cut, and take it off there.
Im not sure if i can describe how i woud make this cut. It involves pulling the saw 3/4 of the way out of the cut, and cutting most uf the way down with just the tip, then plunging in for the last 8". Then go back to the top and finish the cut making sure to use wedges to keep from pinching your bar.
If that doesn't make sense, another way would be to make an under cut about 1" lower than where you plan on cutting. Go in about 6". Then move to the top, and cut cut it. Once you get in far enough, drive a wedge in it and finish the cut. Either way, rhe root ball will probably stand up so make sure everyone is out of its way.
Im not sure if i can describe how i woud make this cut. It involves pulling the saw 3/4 of the way out of the cut, and cutting most uf the way down with just the tip, then plunging in for the last 8". Then go back to the top and finish the cut making sure to use wedges to keep from pinching your bar.
If that doesn't make sense, another way would be to make an under cut about 1" lower than where you plan on cutting. Go in about 6". Then move to the top, and cut cut it. Once you get in far enough, drive a wedge in it and finish the cut. Either way, rhe root ball will probably stand up so make sure everyone is out of its way.