So I knew there was some rust in the bed but I wanted to know just how much. Four screws later and I was able to pull the plastic bedliner to look.
As suspected, this was a bit more extensive than I had originally thought but was greatest closest to the tailgate. Initially I thought I could fix this using one of those patch panels before I read about poor fitment issues. Then I realized I would probably have to replace the entire floor.
The front of the bed looks a little better but my biggest concern is the damage to the flanges along the inner fenders and wheel wells. The wheel wells are easy enough to replace but I want to keep the original fenders. I was thinking of possibly welding in some L-channel and blend that in where needed but if there's a better way I'm all ears. On the plus side, I bought a new Miller welder earlier in the year in anticipation of another project.
Alternately I may look into a wood bed in the future but for now I just put the bedliner back in place since the truck is garaged and I don't drive it in the rain. Plus I don't have to look at it lol.