Correct Brake MC

[Steve Sherman <Steve.Sherman@nsc.com>]

I'm about to replace my brake MC and have the replacement in hand.  It's
an ATE, orig equipment but not stamped with the Audi or VW logo or part
number.  

My concern is that although it checks out as the right replacement (by a
couple of parts guys), at least one other place claimed that my 5KTQ
WAGON took a special heavy duty MC...  

When I do a visual check on the new one vs the one in the car, the new
one looks like it would fit, all the connections in the same place, but
the original one has an extra hump in the casting on the bottom, between
the two bleed screws.

My question is do I have the right one?  Is the extra "hump" just
different OEMs or was there really a HD version of the MC for the wagon?

Any experts out there on brake MC's?

TIA

Steve