What I've been up to...

I started dissecting the driver side quarter panel. Looks slightly worse than the passenger side

More patches slapped right over the rusty spots. Patches over patches actually.

The body filler was really thick here. I'm thinking maybe there's a big dent hiding under it

I wonder what's behind this spot

No surprise to me

Ugh what a mess
Both the inner and outer metal of the fender lip was pretty rotten so had to be replaced

Pretty happy how it turned out. You wouldn't think it (I know I wouldn't have) but just this one patch took me a couple hours. There's a mild "s" curve to the backing piece and the upper piece had to be arced just right to keep a consistent gap along the skirt, then welded together, ground, slot cut for skirt pin, and welded in place. If I was a pro it'd probably go a lot quicker but still, I've definitely gained an appreciation for why proper rust repair is so costly.

Substantially more difficult was creating the piece to repair the inner fender. I will make it out of 5 pieces of metal because of how crazy and complicated it is. This is actually my 3rd attempt which is finally working out. The problem with the first two attempts is that the fender lip would flex a bit as I tested fitted so I could never get it to fit properly. Eventually, I had the revelation to weld a little strip metal onto the lip to keep it in place and that made all the difference. Including the time wasted on the failed attempts, I've probably spent 6 hours on this piece so far and it will take a couple more to finish it off and plug weld it into place.
Not making my work easier is the weather. I work in a 40 x 120 metal quonset building with no insulation and is about 25ft tall in the center, so it's impossible to heat. I have these two 80000 BTU kerosene heaters and use a fan to help distribute the hot air -- otherwise I'd roast on one side and freeze on the other. When it's in the low 30's, with these going full bore it might reach a balmy 50°F in the area I'm working. A little(!) beer helps numb the senses and also dulls the feeling of frustration when I have to redo something I have spent hours working on