That is going to be a major pain to polish (at least it would be for me). If you can afford it you should probably let a pro do it.
But...if you have more time than money (like me
), or just have a lot of time on your hands, I suppose you could get most of the inter-spoke areas with cartridge rolls on a die grinder and/or felt bobs with greaseless compounds. I'm assuming those aren't real "spokes", but if they were you would take the wheel apart to polish the rim.