I'll have to take a look at mine later, although my car probably wouldn't be a great example since I purchased it second hand... Do not know if previous owners ever replaced the windshield. But I'm in the process of taking apart the car for paint so I'll take a look. I did notice that on my panel there are 2 clips on each end, they are white, that do not seem to press into anything. There are green clip holders but the push clips from the panel do not reach. They may just be broken, IDK.

As for bringing back the shine in the plastic, although I have never tried it, may be using Rust-Oleum trim and bumper paint. There are DIY videos on Youtube. Mine are slightly faded as well. Basic plastic trim products will brighten them up as well, but will fade as the product evaporates or washes off. I really dig Chemical Guy's Silk Sheen product for plastics and trim. Darkens the black in plastics and rubbers but is more of a matt non gloss finish. Problem is is that it is water based so it evaporates quick and you find yourself using it often, gets expensive. A better option is, as mentioned above, using some sort of plastic and trim restore and then sealing it in. Here's a link to detailing forum with some product suggestions.

https://www.autogeekonline.net/forum...c-coating.html

 

I have a gap... I also have an aftermarket windshield. Whaddayagonnado, lol.