This is my first design. I had trouble modifying the original STL file so I just redrew it to the dimensions of the original board and cut out the slot for the ears of the breadboard so they could be inserted in any location without having to worry about which way the ears are facing. I'm printing on a Prusa MK4S with a 0.15 speed setting.
The author remixed this model.
I re-created the board holder based on the original. I wanted a holder that you could leave the ears on the breadboards and they would fit into slots on any side of the holder. I tested it with ESP-32 boards, Arduino boards and even Arduino Nano board.