Could some one tell my what is the best thing to use to clean-up a copper plated chassis that has been seting for years and has rust build-up, without damaging the componets.

There is a resident expert on here at cleaning chassis his name is Perter G.B just ask for him

:Could some one tell my what is the best thing to use to clean-up a copper plated chassis that has been seting for years and has rust build-up, without damaging the componets.
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