I am planning to replace floor and toe board and kick panel on the passenger side of my 53 3100. Is there enough rigidity to do this without additional bracing?
It depends on your individual truck . Some high end restoration shops I've known will remove the doors and weld in X shaped supports and remove them after the entire cab's weld repairs are done .
I don’t have to do anything with rocker panel or inner cowl brace. Just wondering if there is enough support to hold the firewall with nothing moving when the toe board and inner kick panel is cut out.
I answered your question in detail . If you can stand up through the trannt hole in the floor, maybe just closing the doors will hold it well enough . The cab can and will twist out of shape if it gets the chance .
Since it is on one side only you can replace ONE SECTION at a time. Start with the worst one and after it is done do the second but wouldn't cut out all three at once. If the outside of the cowl is not rusty it will support the door pillar. If the floor where the battery box hole is still has some integrity it will support the pillar at a right angle to the cowl. Here is a pic showing the sheet metal layout in some detail. The out cowl skin has been removed to replace BEFORE cutting the inner, floor, and toe board. Not the bottom of the door pillar is spot welded to the rocker and the floor is rusted away as is the kick panel and toe board to firewall. The outer cowl was first for repair, then kick panel, toe board, and finally floor pan. The vehicle is a 52 Suburban that was pretty rough; note dash and floor pan. Dash, floor, kick panel work finished:
