I designed this to use my HOSAS VKB Gladiators on my playseat challenge. I used the following hardpoints to mount it on.
https://www.printables.com/model/364829-playseat-challenge-diy-hardpoint
You will need m3 35mm with nuts. (I used four per side to mount, it is sturdy, but you can choose to use more.)
This is for the right side, mirror the print for the left. I printed on PLA with .20mm layer height and 30% Gyroid infill.
The author marked this model as their own original creation.