The first repairs to the floor were at the sides. The area just in front of the wheelhouses and just in front of the floor hump (the one that runs side to side). They appear as the small shiny squares in the pix. Also the wiring shields which are those long strips of stamped sheetmetal that have notches stamped in them. They have tabs that are pinch welded to the floor. Several of them were broke and needed repair. Those wiring shields are bent over flat after the wiring is installed and are covered by the carpet.
In these pix the holes in the floor where the seat bolts have been repaired. And the repair of the sides of the front crossmember (this one is for the floor not the engine) has been done. Like the repair of the uni-body frame at the back of the car, I had to take measurements of what was left of the original piece and have them made by that same metal shop. They did some good work. At this point I hadn't completely opened up the front floor for replacement. I only cut out enough of the floor to get full access to the repair area.
Here I have cut the old rusted portion of the floor away. I used the replacement floor panel to trace a line around it and then cut the floor out about 1" smaller than the trace line. This would be the welding lip. In the second pic that black line you see around the opening about 1" above it is the trace line.
And views of the sides. One other thing worth mentioning is that I loosened the torsion bar adjusting bolts all the way before I cut the old sections of the crossmember away so as to relieve tension on the crossmember.