Another possible rust weakness?

Well, 2 really. Spotted a small raised area on the leading edge of the drivers side rear arch. I noticed the part of the flat folded lip had a small gap between the 2 steel skins. The passenger side is fully folded flat and sealed as per factory.

As I had the liner off to treat in between the steel, I noticed up around the filler flap from the inside another exposed seam which was a tad crusty along the base. Something worth checking too.

Has anyone else had this happen with the arch (lifting away from the panel?)

Edited 8 May, 201313 yr by Liverpool-Lad