Jim and Fellow Listers,

The wrench required for bleeder valves, both clutch and brakes, is 7mm.
At the recommendation of some Porsche pals many years ago, I went to
Snap-On and purchased a 7mm Box End wrench with a 1.5" offset.  It is
perfect for brakes and clutches.

IMHO:  This is one of the most valuable tools you can purchase if you work
on German cars.  It's kind of pricey, but still under $10.

Regards,
Jon Kanas