Removed body off chassis to start body floor structure, did plenty of planning for mounts and to maintain as much original steel in the car. I used 1x3 rectangular tube for cross bracing that doubles as body mounts and nests into the modified original steel. 1" square tube and 1/2" square tube make the trans tunnel and firewall support. I had considered using only sheetmetal for the floor structure but for ease of fabrication I chose this route

This is the layout for flooring, you can clearly see the seat tabs and original body mount holes. I will address the trans tunnel when I get the shifter and I mount the body back onto the chassis.