I purchased a 1988 Mariner. It sat (unwrapped in Wisconsin) for several years. The white panel attached to each side of the boat on the flybridge railing is heavily oxidized and needs to be restored. I have tried buffing with 3M, and it removes a lot of the oxidization, but still is stained. I thought that painting might be the best option, but I need to know what material it is made of so that I can get the proper materials. It seems to be a material that was originally painted, possibly fiberglass. Can anyone help me? Thanks in advance!