A re-post: W123 flooded trunk due to "pilot error"...
 

I screwed up my post on this this morning, but thought it was interesting enough to bother reposting.

Trunk of my "new" 240 flooded after last big rain...seal at bottom of backlight OK, no other leaks evident. However, I had something bulky in the trunk at the time, and though it was not big enough to mandate forcing the trunk closed by brute force, it DID bow the lid of the trunk slightly upward...enough to open the trunk lid seam between the hinges in a way that would "scoop" in rainwater.

Bailed it out, moved cargo around...will wait until next storm to see if this is the problem.