I watched a car show several years ago where they took a bunch of stuff to be chromed to the place in Tennessee that several car shows use (Advanced Plating I think). One of the items was a badly pitted pot metal piece. They stripped the chrome off, sanded the part smooth, treated the pits with something to keep them from coming back, copper plated it, fixed the really bad pits with solder, and then copper plate / sand / copper plate / sand... Eventually the part was smooth, but it was a lot of work and probably very expensive.
