This print takes one of those small regular breadboard lab buttons and enlarges it into a bigger size. The button may be a bit loose, I added extra space to make sure it would fit through and not get stuck. You can always make the top hole a bit more narrow.

button_case is the case
button_inset screws into the case and will only be visible from below
button_button is the actual button

How to assemble:

1. Print the 3 parts (use different colors for button_case and button_button for extra fancy.
2. Solder wires on the mechanical button, make sure they're not too thick or they won't fit through the holes.
3. Slide the wires through the holes of the inset, the button should slide into it.
4. Take the button top that you printed and fit it onto the button (there's a mounting hole in the button where the tip fits)
5. Slide the case over it (make sure the button doesn't fall off the mounting hole) and screw it in.
6. If the button won't click, try rotating the button piece a bit, since the mechanical button needs to be rotated to a certain angle to work.
7. There's a hole at the bottom of the case where the wires can slide through.

Let me know if this worked for you!