On my boat, I used rubbing compound and elbow grease to remove the oxidation. A good buffer would probably be a plus...Then I cleaned it real good to remove all of the rubbing compound. There was still some oxidation left so I took a sander to it and removed the gelcoat down to the paint..In some places I went too far(I'm sure this wasn't the professional way to do it, but it got the job done for me...Heck, it's just a fishing boat:D)..I cleaned it real good again and then I put about 10 coats of Poli-Glow Boat Polish on it. It turned out real good but time will tell how long it will last. The directions said to re-apply 2-3 coats every year. Here are some before and after pics of the finish before the seats and accessories were put back in it::
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