Try scotch-brite and a heavy duty degreaser. Just be careful you only touch the rubber. It will scratch the gel coat.

The lacquer thinner won't hurt anything. If you get some on the gel, it's ok, just don't leave it on there. Wipe it off, and the remainder will evaporate quickly.

Acetone, will melt most anything if you leave it on there just a short time. It works great to clean, but use a rag just dampened with some, and make sure none of it stays on the surface. I personally don't like to use acetone because I know if I spill some in the wrong place and can't get it up quickly, I could do some real damage. Don't let either chemical come into contact with any plastic or plexiglass or it will be ruined.

By the way, if you have a pinstsripe that won't stay stuck, you can take a rag just slightly dampened with acetone and wipe off the surface, then take a Q-tip, and dipit in acetone, let the excess dry up, swipe the bottom side of the pinstripe with the acetone-dampened Q-tip, stick it on, and most of the time it will stay forever. Works much better if the surfaceand pinstripe are both warm.

The company that makes most of the rub rail is Taco they have plants all over the USA the main one is in Miami, Here at Geo we clean rub rail with laquer thinner, if you have any scratches use 600 grit sand paper and rub with a little compound, If you want to you can hit it with a buffer, that will make it really shine and remove the dirt as well

I clean mine after every outing and also use SS w/bleach for the tuff spots. Works great but with all that bleach splashing around make sure you wear old clothes - or you can wear new clothes and make them old in just a few seconds.

I use Acetone, but be sure to wear gloves, very volatile chemical.

Rub Rails and Anything Else
 

I keep a can of GOOF OFF in the boat along with a roll of paper towels. I wad up a paper towel and pour a little Goof Off on it and most anything will come off. Goof off will even take scuffs or stains off of your upholstery especially if you have white seats without harming them. You can get it at any hardware store is costs about $2.50 a can. One can will last you a long time because you don't need much when you use it. Beware of immitations, I have tried them and they don't work, Goof Off works the best. Eric