Thanks, Hirnbeiss, for the part number and comment..Its just the rubber lip on the part which contacts the glass that is degraded and crumbling. I am feeling there may be a way to replace just the seal after cleaning out all the crumbled remains and the debris clogging the drain channels and tubing.

The car I found has had dealer maintenance plus a service contract, the costly fixes have been properly done) yet nobody maintained the little stuff and its been used hard although low miles and a great price so I need lots of miscellaneous parts. (engine cover tabs are broken and it rattles..) And for example I discover Mercedes does not sell the door mirror gaskets which also degrade and crumble. A couple E-bay sellers have picked up the ball and are offering these parts, plus instructions to change them out. (no luck with our friend, Pelican)

The forum here and MB websites have been invaluable sources and the information steered me clear of options like the often underpriced '06 E350 with potential balance shaft issues and other maintenance nightmares that would ruin a low dollar guy like me..Im so grateful and glad to contribute whatever I can to the efforts and for their understandable limitations, greatly appreciate the good work at Pelican.

I truly believe every problem contains its own solution...even as applies to German cars!

Thanks all!