My fab shop is doing that for me now with the old chainplates. What still surprised me was that the sealer around the chainplate had become so brittle, it was almost dust. Equally amazing is that in that condition it was still keeping water out (or maybe it wasn't anymore). I would venture that 3M 5200 was used originally or something similar. I wonder if the chainplates heating up in the sun over many years may have totally baked the sealer?
