I got the following reply from Hella a few years ago.
Thank you for your inquiry.
These lamps are relatively simple to convert from UK dip to continental
dip. You will need to remove the dip beam light units from the vehicle.
If you have a four-headlamp system this will be the outer light unit on
each side.
On the back of each lamp, you will see three screws. Two in slotted
holes and one in a circular hole with an unused hole next to it.
Undo the two screws in the slotted holes slightly and remove the screw from
the circular hole fully.
Now twist the light unit so the screws in the slotted holes are at the
other end of each slot and the unused circular hole now lines up to the
hole in the front body of the light.
Replace and tighten all three screws removed.
To convert it back to UK dip reverse the process
It is possible to do the job described above without removing the units, depending on access.
Here's a link from many many moons ago on another forum
https://www.motorhomefacts.com…245/page-3