Wear a mask and eye protection. Gloves help too. It might be wise to spill some in the right places. Rubber abrasives are going to save you time smoothing the cylinder once the surface has had most of the sharp edges removed. Jewelers rouge is a cutting tool to aid in the removal of metal without leaving too many marks.
Some hardware stores have big chunks of the stuff real cheap.
Again a light touch and keep the tool moving. I only did it to one cylinder and head one time, and it was time consuming. We can dig the amount of work involved. Just don't understand it. A black coating radiates heat several times better than a polished surface.