To be honest i dont think you can beat a proper job and wet sand them, i done mine last week, started with 800 grit then 1000, 1200, 1500, 2000, 2500 and then polished out with autosol, it was a long process took me the best part of 7 hours to do both of them but they now look brand new, will get some photos uploaded and show the before and after, mine were shocking they looked like the previous owner had cleaned them with a brillow pad or something and over time they had just turned a nasty yellow, look clear as day now!