On some of the smaller holes, instead of trying to make small plugs, I just shoved a sheet rock screw into the hole as a backer and burner her shut.
Once I got my holes filled in, I fit and stitched the recess box in. I originally had planned on cutting the opening for the box to fit flush into the firewall and then weld the flange all the way around. But upon further review i realized to do it that way would have meant cutting into the ribs that were stamped into the firewall at the factory for re-reinforcement. That just seemed like it would cause more trouble then it was worth so I mounted the flange to the back side of the firewall. I now have it stitched and ground down on the front side, and plan on stitching on the backside as well. Hope that made sense. Maybe the pics will help.
I was able fold over some the extra material on the recess box and create a flange to add more support for the floor boards.
So at the end of a few long days this what the firewall looks like. I still have alot of clean up to do yet but i'm gettin there. Did I do it right????????? I don't have a clue. But I know a painter that's good working with spackle
