Also, that's a great overview photo, but could we also see a closeup showing in more detail what is going on in a sample section? I can't tell if it's stuff on the roof or damaged roof surface.
Even with more detail, I won't be the one with any expertise in this subject, but it will help others who can provide good information.
1979 Boler B1700RGH, pulled by 2004 Toyota Sienna LE 2WD
Information is good. Lack of information is not so good, but misinformation is much worse. Check facts, and apply common sense liberally.
STATUS: No longer active in forum.