[pbs911]

When I did my turn lenses and running light, I used a very course grit on a belt sander, probably close to 400 grit. It removed alot of material but it was necessary to get the pits out. These things are pretty thick. I think the only thing you may have to worry about is getting the lense so thin that it will crack more easily from flying debrie. After the 400 grit and belt sander I moved to the 1500 grit and plastic polish. They look like a mirror now. I also removed the little "SAE 78" from the lenses in the anding process.

Sorry I can't help ya with the bumpers.