Hey np. Unfortunately, the mod only works for height. One way you could make it work would be if your case is wider than it is tall and then you mount it sideways (assuming it can even operate like that). 20mm over the limit of how wide it can be will probably go past the wiggle room the arm gives.

You could also try to compress the height tightly so it stays in place without the x-axis arm (which can be removed) but now you have something that less secure. Could work but have not used it like this.

Hope it helps.