Arduino Mega with breadboard mount

In order to mount the arduino you just press it firmly in place. The fit is very tight as I didn't want it to fall out. Don't be afraid to push the Arduino hard to get it in place.

I took inspiration from this https://www.thingiverse.com/thing:1815636
But I didn't like the need for screws in his version and also i moved the arduino in order to be able to print two at the same time on my Ender 3.