I have the first draft of a rough install on the passenger side done, see attached. I have not addressed the rocker panel or the reinformcement issues yet but at least I have something that resembles a floor and cowl area.
The rocker I am contemplating fabricating a piece that will follow the shape of the outside of the rocker with a flange to attach it to the backside of the inner to outer panel. It may be harder than I am envisioning sa it is prettu much a blind area. The rocker panel itself seems pretty solid from the door pillar back. I think I can get it tight to the inside of the existing rocker and plug weld it to the existing rocker.
The reinforcement appears pretty solid except for the end outboard of the mounting hole, the wide flanges that attach to the floor flange are solid but the end flange and the related center of the support are basically gone. I think I an fabricate a piece to replace the missing material and get a pretty solid part.
A lot of work to do yet but it is at least a start.