I have been working on this, just not updating the thread as well as I could/should. I'll make brief comments on the progress, to keep this, somewhat short.
NONE of the 4 bolts in the trunk floor body mounts would come out, so I used a porta-power to make a little room for the sawzall and cut them off. Floor is junk anyway, so no loss.
I left the right side floor intact for now, to hold the quarter panel in place.
Then I crawled inside to drill out the spot welds at the leading edge to cabin pan.
I "thought" the spot welds I could see on the seat brace went all the way thru...NOT, I had to cut the brace off and drill out more welds under it.
The floor still wouldn't come loose, so I cut the next level off and found MORE welds under that. The floor had been put in, in 3 pieces and all of them had their own welds...
FINALLY got that out. Poor weld flange looks like a shredder got ahold of it. No worries, I'll straighten it out, but weld the new one along the leading edge anyway.
Next, I cut off all the rusted flange areas of both the inner and outer wheel houses.