[A/S] It's the pits

[SHMossLanding@xxxxxxx]

Am polishing our 1965 Overlander, and along the top, about where the canopy 
would sit, it is severly pitted, with what looks like black mold. It is not 
mold and it is very hard.  I have tried stripper, stell wool(0000), 3m pads.  
Nothing seems to remove it.  Does anyone else have this and how do I remove 
it.  Also, nearly the whole roof looks like galvanized metal.  It does polish 
up, but has little white specks and several dark specks which are very 
difficult to remove.  Any idea what critters these are?

                                                 Chuck & Lynn
                                                 1965 Overlander