Don't worry about those habitrails, with good chrome polisher those will be like new. I had little more rusted TZ ramps and here is little peak how those came up. You can actually see used polisher tube in background.
And good luck with machine, it will become nice. Don't worry too much about insert-damage, just level those with little help of hot air, glue (from underside) and c-clam/weight. After all, ball is quite neutral about the surface it's rolling, only bumps or dents are disturbing it. It doesn't mind tha is there all pixels on the place or not. But keep us posted!