If your doing it yourself then invest in a polishing kit, they used to include 2 or 3 different mops and grades of soap. ..expect to knacker up atleast one electric drill as the bearings on the chuck aren’t designed to take the side loadings that polishing will dish out.
Even with the above expect it to be a long, tedious and dirty job. For what it’ll cost I’d track down a local metal polisher. The one’s I’ve used in the past used to charge about £50 for a motorcycle swinging arm, so I’d estimate £60-£90 for your SC. They will also make a far better job of it than is possible DIY.
If you are going to have a go then most motorcycle shops will sell you an aluminium polishing kit but they may have to order it. Should cost about £25.
There’s an article in this months Dirt…they had an Orange 5 polished by Cardiff Metal Polishers, phone number is 02920 867837 looks a top job.
Hope thats some help
Stuart