Hey Benzin, make the masked hole of a smaller diameter, 28mm or even 27mm for a better result.
You will get better aesthetic results (as factory) and the sensor will work correctly.
I had to correct mine to a lower diameter (28mm) so that an outer circle could not be seen that the gel pad could not cover.
Now I post some images ... wait
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My first attempt, Ø > 28mm.
My second attempt, Ø = 28mm.
psss... not perfect, but a little better.
(I'm waiting for the windshield to break, I haven't had such luck during these years ..

)
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read this pg
viewtopic.php?f=56&t=58703&p=502496#p502505
as you can see I edited some post.