I was looking for something that would let me change the mainboard cover to allow upgrading to an 80mm fan from the noisy 40mm fan.
Initially, I found a design that suited a 90mm fan and then couldn't find it again. So I created my own.
This one is a little shorter than the metal cover because I have lots of wires coming from the controller board area and I've added an extra hole at the back to use an M3 screw with a T-nut to pull it snugly onto the bottom of the extrusion
The author marked this model as their own original creation.