This is a bit out of order in terms of what's been worked on but worth a post. The second-worst rust on the car is the rear passenger side's subframe mount. The upper plate is mostly still in tact, but the lower one doesn't exist at all. And the sill is hot garbage. Inner sill is flat 16ga but it gets a bit more complicated as you work your way outwards. Car came with replacement outer sills suggesting it was bad for a long time.
Digging through this site over the winter I found a couple threads on this subject. I ordered a fairly large collection of parts from W&N and their replacement panels for these areas were part of that.
Reference Thread 1:
Reference Thread 2:
Measure twice and check the reference. Turns out the W&N panels are about 12mm (1/2") shallower offset than the originals from what I can tell from the references and rusty part I have left.
In to CAD and off to the machine shop
Back from the machine shop & fit-checking. Here you can see that the offset of the lower panel is different from the original. Have to move the step in the bolt capture to keep the subframe mounting surface in the correct place. Someone cleverer than me could've put a shim here instead for more suspension geometry adjustability.
Bonus photo for the next thing I'm working on. Stay tuned...