Hi it was easy,
to reduce the gap, I'm just drawn a line outside to the window.
I Cut it Right there.
The sawed-off part of the back and put it fixed.
To get around 3mm space between the window and roof I put on bonding spacers between.
Until the glue was dry I had screwed 2 screws for fixing. Thats it
Sorry for my bad english, I hope you can do something with the instructions.
regards
And my daily update.