I got the following info from the Corvette Forum. The member who posted it said that after cleaning his moldy, mildewed and stained top, it looked like new. He got his info from a boat detailer at the marina.
Here's how he described going about it. After allowing the top to warm up in the sun, spray a 50 – 50 solution of bleach and water on the top and let it sit for 20 minutes. DO NOT RUB. Then wash it using 303 Top cleaner. Let it dry in the sun then apply Fabric Guard top spray from 303.
I won’t be trying this method until I get my next convertible but it sounds like it should work. I think I would use a 1 part bleach and 4 parts water to start. Hate to see my convertible top disintegrate before my eyes.
Here's how he described going about it. After allowing the top to warm up in the sun, spray a 50 – 50 solution of bleach and water on the top and let it sit for 20 minutes. DO NOT RUB. Then wash it using 303 Top cleaner. Let it dry in the sun then apply Fabric Guard top spray from 303.
I won’t be trying this method until I get my next convertible but it sounds like it should work. I think I would use a 1 part bleach and 4 parts water to start. Hate to see my convertible top disintegrate before my eyes.