You can swap the motors left to right! However that causes 2 problems:
-The sqirters will never fire because the trigger for them is part of one of the motors, the passenger side one as I recall
-The sweep of the US motors is a lot less then the euro ones. They will only clean 1/2 of the lens
What I've done on my car is combine the parts from some euro motors (the different gears) with the longer shaft from the US motors so I can still use the US mounting brackets and trim strips. I then got wiper arms from a late W124. It's not exactly the same as a true euro setup, but it works well and does clear all of the lens.
-Jason