Guess I should show you my 4R frame, looks about the same underneath…. Then you get above the spare and behind the rear bumper cover….scales just peeling off. Rest of the frame is “surface” but I have some nasty scaling up high where the PO never got under the truck. My front crossmember is also due for replacement soon. Rust kills these trucks more than anything else.
As to what happens to rusty “nice” trucks, we’ll there’s a 100 in CA that came from the NE and it’s been posted for sale a multiple times. I see the same rusted 100s sitting on lots around here. There’s at least 3 I could point to that have been on dealer lots for over a year. 200s will follow suite as they age and people look towards newer trucks.
Sure you got a deal, for now. I did the same with my 4R, it was cheap with rust, now I’m planning to dump it(not a good feeling knowing the engine has plenty of miles left). It’s overall cost surpassed my wife’s 4R that I paid 3.5k more upfront. It’ll catch up rust always does. I’ve also ignore some big ticket items like UCA replacement (did lowers, totally seized) never fixed the header tick either. So all in all its closer to 6k more expensive than its rustless counterpart.
I think you’ll enjoy the truck, just be ready to let it go to a dealer in few years.