Paint or stain and topcoat can be removed with most methylene chloride-based strippers, such as:
Dad's Easy Stripper™
3-M Safest Strip®
NOTE: If selecting other products to strip the stain, make sure to read the warning against use on fiberglass.
Remove the stripper within 2-3 minutes. Follow the paint stripper manufacturer's directions and cautions for use of the paint stripper. Use a clean rag to apply the stripper.
Work on small areas at a time. Follow the pain stripper manufacturer's directions and cautions for correct use of the paint stripper.
After the stain or paint has been removed, scrub the door with an all-purpose cleaner to completely remove any stripper residue. Rinse well and wipe dry.
Make sure door is completely clean and dry before refinishing.