UPDATE: It was WAY rustier that i would have imagined. been kinda lazy and not even close to finished. the passenger side is almost done. It took 3 big patches, some fiberglass, and some bondo. but its under the skirt so i dont care how clean it looks. As for the driver side, i think it may need 2 or 3 patches as well. the rear quarters weret as bad as i thought and just needed a thin layer of bondo to fill where the rust ate away the metal.
Whats funny is, on the drivers side, i found a patch where this has already been attemped to be fixed. I am assuming that Mazda did it with the rust warranty or whatever. So if any of you has had that, dont trust the work from mazda. and the holes that the skirt clips went into is what was really rusting bad. so your skirts maybe loose on the bottom. Might be worth taking them off to check them out. the only reason i took mine off is that i could see the rust starting to creep up just under the back of the rear door.
Pics to come.