Kool Stop Salmon brake pads are far superior to old Campagnolo brake pads (or any other old/hard brake pad). When I come across a rim that has markings on the braking surface caused by various objects in the brake pad I use a double sided foam filled sanding block. These blocks can be bought at any hardware store or Walmart and several other stores. Submerg the block into either just water or a mild soapy solution -- using a side to side motion -- apply pressure with the sanding block to the braking surface. It will take only a few strokes to clean the rim (some deep gouges may still be there but all but the worst markings will be gone). Then move over to another section until rim is clean. Both sides will take only a few minutes to clean. Braking will be quite and efficient.