@kamkar1, that looks great! I'm glad to see someone actually do this.
I have a couple of suggestions.
The "brushed suede" black dash mat I bought worked really well but there was still a bit of reflection from the nap in the fabric and being the hardcore dash cam fanatic that I am I did something that I knew was a bit extreme but that worked out far better than I ever expected. I sprayed the dash mat with two coats of
Rust -Oleum Camouflage paint!
I thought it would make the dash mat look hideous but instead it came out beautiful! The mat still looks like nice (faux) brushed suede but it now is MUCH better at eliminating reflections. I was kind of amazed that what I thought was a questionable thing to do would work out this well. Basically, the paint absorbed into the fabric instead of creating a crusty layer on top and this is why it came out looking so nice. It's been a year now and it still works and looks fine. It might be worth a try. You don't really need extra flat camouflage paint, any flat black spray paint will do.
My dash mat came with long strips of Velcro that I really didn't think I wanted to stick to my dash board but I happened to have a roll of gray 3M VHB tape that I found in the clearance isle of a local Walmart. This stuff holds extremely well on the plastic surfaces in my vehicle and it is what I use for the dash cams that I have mounted on plastic like with my side cams. I discovered though that this stuff (unlike the black 3M VHB tape) pops right off easily from interior car plastic without any sticky residue or difficult peeling. So this is what I used to secure my dash mat (just a few small pieces) and after a year I recently pulled up a piece just to test and it came right off so that you would never know it was there in the first place. Maybe you can find something similar. (I wish I knew the 3M product number but it is not printed on the tape core.)
Finally, I used a plastic kitchen spatula to push the edge of the dash mat down between the narrow gap between the dashboard and the windscreen glass and that worked really well to get the thing properly seated on the dash board and serves to hold it in place as well. There was an issue with the dash mat blocking the flow of air from the vent against the windshield but the spatula fixed it.
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