It depends on what the desired look is when finished. If the desired look is like original, then the scotchbrite is the trick. If however, the desired look is truly polished, then a sewn spiral buff and tripoli buffing compound will bring it up to a mirror shine that you can see your face in.
I'm with Ray and John.
I used a scotchbrite pad on mine and in some very bad areas also added a SMALL amount of metal polish just to help clean up better.
Mine came out pretty decent but not as perfect as I would have liked but it was still a significant improvement and it looks much better than before I started although some areas that were really bad still left some stains.
I was just afraid that if i went any more agressive that it would look too overly polished and shiney which wasn't what I was going for.