I just took out my windshield wiper linkage to make some more room for working on my blower motor replacement, and this writeup is spot on. Make sure that you get a 15/16" or 24mm long socket, because conventional sockets won't be able to reach the shallow bolts that hold the assembly in place. The 10mm screw and washer on bottom side of the cowl is not too hard to reach, but it does take some time to extract. Of course you will want to be very careful that this part does not fall down, else you may have a difficult time finding it again.
Thanks to OP for the excellent writeup and for everyone else's insight. I did not stop my wipers at the 12 o'clock position as suggested by some members here. I think that the home position is a little different now, but it's not having any bad effects on the wiper movement. In fact, all vibration that was once in my wipers has stopped. Now I only hear the sound of the wiper blades switching direction at the end of movement. Wonderful!
bullet proof one piece at a time
my page on BMW Performance parts for the E46: clicky