So I have a Catalina 22 stored in a 12'x26' canopy, the other day after some rain and high winds came thur I went to check on her and found that a robin has been hanging out in there. Long story short there is bird poo all over the foredack and cockpit. I've washed it with some boat and hull cleaner but every were there was a spot there is now a stain. Is there something on the market that is good at taking out hevay set stains or am I looking at something more.