I remember being part of a team that polished a Lightning fighter (English Electric / BAC , not Lockheed) with "Wadpol" for a Royal visit to RAF Valley in Angelsey (next to the sea) in the early 70's. It looked fantastic for about 4 days then started to form surface corrosion. Polishing took the thin protective surface off the Alclad metal. Soon after that Lightnings were painted rather than the natural metal finish. Paint was better for anti corrosion but they never looked as good as they did in bare metal. About the same deal with the M3W I would think.