Discussion about the Korg PolySix synthesizer

Hey, my Polysix has pretty badly yellowed buttons and knobs (from UV exposure over time), and I'd like to restore them to the original grey/white. The keys are kinda off-white too. Has anyone had experience with Retr0bright (http://retr0bright.wikispaces.com/) to turn them back to their original colour? Or any other methods?

Thanks