I scraped (not scrapped) the frame on the passenger side. Sprayed it with Ace Rust Stop. It has good reviews and didn’t ask for tons of prep.
Tomorrow, I’ll do the drivers side. Then, crossbars and the rear diff, plus a few spots in the bed.
Honestly, I’m impressed how good of a condition everything is on the under carriage. Only thing that rusted out were the clamps holding the heat shields and I fixed those last year. Exhaust, all of the hangers, everything looks great. But now I want to paint everything and refresh her a bit.