Earcups are too close for my ears, and it gets painful to listen for a long time, so I made a solution for us to use. The design is symmetric for both earcups. Took me 3 tries to find out the best way to print this, 2nd picture shows the best way I found for accuracy with fit and finish. (After installed may not fit in the case after this modification, and also gives trouble with folding up.)

Feel free to adapt the idea to fit it to your own application by analyzing the design.

Printed with automatic supports, like the 2nd picture. The screws bit in the best on this orientation for me.