Had a chance to get out and play stabby stabby with the floor tonight (poking with a big screwdriver to check for weak sheet metal). Didn't break through anywhere; the floor seems pretty solid.
I also cleaned it up a bit more with the wire wheel to get most of the loose paint and scale off.
I think I am going to go the POR-15 route, but I had a few concerns. I've heard that POR-15 doesn't stick well to clean metal, even when prepped with their Metal Ready and Marine Clean. The problem that presents for me, is that in order to get all of the loose paint/scale off, I'm definitely going to have clean metal in some areas (you can see some in the pictures below, already). I don't want to leave any of the old paint behind either, as POR-15's instructions recommend against it.
Should I just prep how they recommend and hope it sticks to the clean areas?
Floor carnage:
This bit here seems to be the worst section of the floor as far as pitting goes. I think I'll clean this area out really well and run a weld bead over it to give it a little bit more meat. I don't like how thin it is here to just leave it as-is.
