hi Dave,
that´s a well known and common problem with the
so called "einheitskoffer".
the iron linings are foldet in that area (lower edge of the "koffer" all around) what makes the water/salt/mud creep into the gaps and try to disintegrate your hard-earned travel-dream.
repair is normal body work...just cut of a strip 150 mm or so of the lining around the koffer (or where the rust stucks ...watch for small bubbles in the painting) an replace it by a fitting fabric...like aluminium or steel...or ?
in case only the wheel arch suffers from rust - threatement from inside with anticorosives might be the means of your choice...
but time after time you`ll find the rusty pest all around the lower edge...
much success
roman
