Probably the most effective way to remove the build up of polishes on the surface is to make up a solution of Spic n Span...no kidding...and clean. You will need to be careful not to get any undissolved grit on the sponge, but it will remove the build up. When the surface is clean, the Cory polish will work well. It may lack the long-lasting shine of he old Unicon (silicone) polish, but has the advantage of be possible for mere humans to use. Steve
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