corsa chromed rocker cover

Surely you would be better with brushed or polished Ali or Stainless than with chrome?

Unless you plan to polish it every time the engine is run, you will just end up with rust coming through, and/or flakey peeling chrome, and a dull grey finish showing through in splodges.

I don't know what the standard one is like on a corsa but why not polish up the one you have? A few hours and a bit of elbow grease later you will have it looking quite nice, or if you are happy to devote a weekend to it an almost mirror finish. Me I'm lazy so it got 20 mins with a dremmel type tool to make it look presentable.

Guess what the Ka's rocker cover is doing :P? I don't think I'd get far polishing it to a mirror finish...