Some of the pumps (I can't remember if it was the Vickers or ZF) have the reservoir welded to the bracket, so you have to take the whole bracket off. This is not fun, but the links below will give you some help taking the pump and bracket off. I know the return line hooks up behind the reservoir (first picture in first link). I don't even know how you managed to get the line off.

http://www.peachparts.com/shopforum/showpost.php?p=1979072&postcount=4

http://www.peachparts.com/shopforum/showthread.php?t=164607&highlight=400e+power+steering+pump

__________________
1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles