You can start with some aggressive metal polish (Simi-Chrome or Wenol Red) and work at right angles to the scratches. Better, if they are available for a cotton buffing wheel (either a drill attachment or a Dremel tool for small areas), use a buffing wheel at right angles to the scratches with the aggressive polish.
Follow this with Mother's Billet or the new Meguiar's NXT Metal polish. Check your progress frequently.
I typically finish my polished billet with a buffing wheel that is "loose" cotton instead of spiral sewn.