They are probably referring to the fact that the headlight wiper mounting needs to be modified in order to retain functionality of the US wipers with the Euro lights. This is an easy DIY task.
The alternatives are 1) do without wipers, or 2) install the matching Euro wipers ($$ several hundred). You'll find a discussion of the modification procedure and the advantages of Euro lights by searching 'Euro Lights' and 'barrie'.
Hope this helps.
[This message has been edited by barrie (edited 07-11-2000).]