I used paint stripper and wire wool to take off brake dust and clear coat. Then wet & dry, getting gradually finer. Then metal polish. Then tape-up and paint the coloured bits (I went black background, red pin-stripes). If the metal spokes are well polished, any paint you get on them will come off with a finger nail. You'll need several coats on the pin stripes, as the paint can roll down them whichever way you dry the wheel. I'm happy without clearcoat on top - but that's a personal choice. Oh - and get a good face mask, aluminium dust is NOT pleasant .
There are links to pictorial guides to this on www.celicasupra.com