My '03 Accord recently had a MOT advisory for discoloured headlight lenses. Duly advised by the hondKarma site, I purchased a refurb kit from Halfords, a "Maguires" product. The kit cost a little over £20, and comes with a rubbing/polishing fluid and a wool backing pad for insertion into a drill. The whole exercise took a little over 20 minutes, and the lenses are like new. One word of advice, don't do this in direct sunlight, it makes it hard to see the last remaining marks that still needs polishing off. A really good product. I have attached a "before" and "after" photo. Thanks to the site gurus for the assistance, yet again!