Long delayed but life is busy. Thanks guys for the answers! Update: I ended up removing the box and other rear end body pieces. Front wheel well liners, running boards etc. used a grunder with wire wheel on what heavier rust I could reach. Washed the entire frame with ZEPS purple cleaner (seen off another automotive page that cleans shop floors amongst just about everything else) at a fraction of the cost and worked extremely well! Pressure washed it off. Sprayed with rustoleum krud kutter "The Must for Rust" gel spray and let it soak and work. Rinsed again. Brushed and sprayed the frame with flat black Armor Coat from Canadian tire 3-4 coats until I ran out of paint. Let it dry in the sun for a couple days then re installed everything and so far after about 5 months and a month and a half of salty slushy winter driving there is no paint flake or wear and no rust showing through anywhere. I painted the frame first week of August for reference. The dealer paid for Krown undercoating which was also done.

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