I used ABS plastic. I can't remember the thickness but it's the thinnest one, 1/8th" I think.
I did think of the Velcro but decided to use the 3M double sized tape for ease of install.
After I get to my new home I want to do something removable. Only thing is its difficult to do something that you can take off and also leave nothing Visible behind.
4000KM road trip starting tomorrow, I'll post pics and results of my new unposted mod (diffuser) when I get there. No Internet right now, using phone
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