Best bet for a good final finish is probably to take them off as you say, polish them to a very high quality gloss using a bench polisher, several different mops, and progressively finer compounds. Then you need to thoroughly degrease them, re-fit it while wearing clean gloves, degrease them again then fire them up and give them a good long, hard run in dry conditions...this won't stop the discolouration but will make for even discolouration. Loss of the will to live may then follow and an acceptance of heat coloured pipes.
An added refinement would be to get a system made up in titanium, go through the polishing and cleaning steps and then see the spectacular colours that result!
