I combined the design by rt4me, and the design by DAcreates, with a couple changes to both to make this. I don't own a Focus RS, but a friend does, and this seems to work well for him.
When I printed the original design with my Ender 3, it broke pretty easily. I've since realized that this was probably due to an under extrusion issue I was having, but all the same, I made the walls a bit thicker to hopefully help the strength a bit. I also made the whole thing a bit deeper.
I filled in the line from the RS logo to keep anything from getting caught up in there, and make for what I feel is an overall cleaner look.
I'm not sure what years this would work for exactly, but if anyone knows, leave a comment and I'll update the description.
40% (lower would probably be fine)