The lower panel is now upholstered and installed. We used velcro so there are no screws in sight, which is good! Mmmm do not know if the foam is thick enough, it looks different then what I had in mind.
Here are some examples I found online of GMC-ers:
The wooden blinds 2,5 cm (0,98 inch) are ordered and will be fixated at the bottom with a little plastic pieces. This system is because we like them mostly all the way up and no frames visable. The only piece missing now is the OEM window trim from unpaintable rubber. Which I think has to stay white for now….