Back on the rust repair! Finally bit the bullet and started working on the passenger side rocker. In my naive optimism, my plan was to cut out this small section, and weld in a simple patch and be done with it:
Of course, it's never that simple. Here's what was lurking behind the rust:
The floor pan flange, which attaches to the rocker, was also Swiss cheese, so I had to enlarge my patch in search of solid metal.
In the end, I had to replace about 10" of the floor pan flange. It was a tricky spot to weld, so I ended up doing a lap weld instead of a butt weld. It's nothing that anyone will ever see, since it's inside the rocker cavity, so I'm not concerned about how it looks. I'll be plenty strong, though.
Here is the final outer patch, partially welded in place.
There is a brace behind the rocker that connects the rocker panel to the floor cross member, and of course that was rusty as well, so I recreated it as best I could:
Here is the brace welded in place behind the rocker. Probably some of my worst welding yet, frankly! Haha. I blame the tight quarters (the passenger side of the truck is crammed against the wall) and poor lighting. Anyway, it'll do the trick. I also plug-welded the floor pan flange to the rocker.
Finally, the patch fully welded in and filled. Definitely not my best work, but still quite satisfactory. Nearing the end of the rust repair, finally, with only the driver's side quarter panel left to fix! Then it'll be on to mechanical stuff and wiring.