You know that's a great question Ron, real mag's (Magnesium) are a pain to keep up. Back in the day, I helped my dad's friend that raced a McLaren Mk.1A, and that was part of my job, literally the minute your done polishing Magnesium wheels they start oxidizing. And a rough surface doesn't help. Let me do some homework, with the vintage racer's that have real Mag's, and see what they use. I can't remember what we used on the McLaren (You know the old memory isn't as good as it once was
) Cheers Tom.