Pretty niche need. My friend wanted his computer tilting to help his AIO and keep the cat off.
It fits perfectly.
I printed mine at 20%.
If you don't want the support grid to show through probably make sure you have 3 walls or more.

255mm long, you will need a large print bed to handle this.
Recommend printing with a brim to prevent corner peel.

I placed 4 square rubber feet on so it wouldn't slide
(Amazon link here: https://www.amazon.com/AmazonBasics-300-Piece-Adhesive-Rubber-Bumpers/dp/B087MG3G76/)

If anyone wants me to cut it in half so you can glue it I can, but you'd be losing support and I don't have good luck making puzzle pieces that lock into each other.