Thank you, I think option 2 is the route for me.
I'm still a bit worried about the lower edge of the B-pillar (that I tacked in) being correct. As you said, your gap wasn't was bad. The b-pillar patch panel matched what was left of the original metal very well. It also matched the natural bend in the new floor section as you can see in the pictures. That is why I thought I was good until I tryed to install the brace.
Do you think my b-pillar patch looks correct? Maybe I need to modify the b-pillar patch and do option #2.
