It can be done and I have a stainless Colt 1911 that is so shiny I thought it was nickel plated. Anyway the key is in removing all the scratches first before you polish it. Scratches are magnified by high polish. They just stand out more because of the greater contrast. Remove them and then polish.
Vigilantibus et non dormientibus jura subveniunt. Molon Labe!