I have an '01 and an '05 S2000, and use 303 protectant on the soft tops, too. I bought a gallon the last time and also use it on our jacuzzi cover and outdoor pool furniture.

After I wash the soft tops, along with the cars, and use the California blade on the tops, and when they're fairly dry, I soak a sponge with the 303 and wipe it on the soft top. I soak it good. It dries fast where I live and looks good.

I buy it on-line here: http://www.superiorcarcare.net/303aerprot.html

 

Check Marine supply places - where they sell boating stuff. You can get it there.

Now what I want to know is how to get the soft top squeaky clean without damaging it. Soap and a rag/sponge just doesn't work. The top also gets a sick rusty brown tinge to it that's really difficult to get off. The 303 keeps the black from fading, it's just the grime that makes it look dull.