After I had removed the torque box cover, I started by removing the spot welds of the door jamb brace and then used a cutting disc on my angle grinder to cut the seam welds on the top and bottom and finally, used an air chisel to pop the part off.
Next I cut the trunk to floor brace in half and then cut away the seam welds at the top and the floor spot welds at the bottom and on the inner rocker and chiseled the part out of the car.
After removing the brace, I cut away the floor back to the rear trunk transition panel.
Finally, I was able to cut across the top of the remaining inner rocker and gain access to the spot welds that were holding it to the top of the outer rocker flange. I then finished up by cutting away the rusted lower flange from the bottom of the outer rocker.
The picture below indicates what the finished job looks like before wire brushing the scale rust and treating and preparing the interior of the panels that are newly exposed in anticipation of the new parts to be welded in. I can see that I'll need to patch the lower section of the inner wheel house as I previously did on the right side.