The plan for this work is to set the passenger compartment flat level, and check and adjust the end rails at the bumpers. This will get the rockers back into alignment. Access for reinforcement will be through the bottom closure pan, which needs to be replaced anyway. A new closure pan will have to be made, which is mostly flat lengthways. At this point I am only intending to do the inner part of the rocker panel for structural reinforcement, and the outer part will be done later when I get to the body.
The top of the rocker in the cowl section just behind the front wheel well (floor of the cowl section) is also rusted through and needs to be repaired to prevent water going into the rocker section. The drains from this section, which drain the cowl vents in front of the windshield have a weep slot behind the wheel well fender section, which has plugged up long ago. There is an overflow hole with a boot on it about an inch or so above the floor of this section resulting in standing water over the years once the weep slot has plugged up. Access for this repair will be through the the passenger compartment by removing the dash, vents, and cutting open the inside section for access.