I would try the soaking and waging before I would polish it. To me that looks like a last resort. as for silicone, I use nothing but pure silicone from Kelloggs in Sandusky, Ohio. Either the #110 or the #105, applied with real lambs wool. I have been using this since 1969, and have never had a discoloration. I do not use silicone with other agents in it. Also, NEVER have had a spot of rust appear

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Pete
I ain't no fortunate son