Hey, before trying the harsh stuff try a Cleaner wax product like Maguires cleaner wax (#50?). Don't ask me why it works, but it does. A straight wax doesn't seem to work
, you need the compound. Straight compound may work, but I like the idea of leaving a little wax behind.
I found this out as I was waxing a boat
and just had the impulse to apply it to a ugly old cowl vent, it worked so well I tried the lifelines and fenders.
Hope this helps,