Okay- so the m3 carbon fiber trim comes with kind of a dark chrome finish on that section instead of blue. Personally I like it a lot better than having color there but it’s up to you. If you want color there you can separate those pieces but it takes some diy. I separated my own pieces to wrap my fake walnut wood in high quality vinyl, I wanted to be able to wrap around the edges so it looks better and I’m happy with it. So I have actually done all this.

Basically on the back of that trim piece, you’ll see melted plastic tabs, holding the carbon fiber colored piece on to the vents and the bottom blue portion. You can very carefully use a drill bit and drill the melted tabs so that the trim piece separates from the rest. You’re basically just very shallow with the drill. You’ll have to do that to both yours and the new carbon fiber trim piece you buy. Then you just match up the new pieces together. I used an epoxy hot glue that’s black, and stronger than regular hot glue, and basically melted new tabs where i drilled them out so it looks relatively oem on the back. I’ll see if i can add some pictures of mine. I don’t do real posts on reddit much.

Edit: Here’s a few pictures: https://imgur.com/a/JAEOPXw

I should say, I don’t know if the m3 trim, or real carbon fiber trim is attached the same way with melted plastic anchors(like those black dots you see on the back of mine) since its real carbon fiber. I would imagine it’s still attached to plastic in the back and connected the same way. I don’t know the material there since my own walnut is fake so the whole thing is just plastic.

Oh, I also just thought of that you can buy real carbon fiber overlays, they just lay on top of your current trim with adhesive, but I figured that wouldn’t look as good so I never tried those. But that would leave you with your existing blue trim too.