Drill first ask questions later
I started by drilling a smaller guide hole on the top of the box, the bottom plate or lid will be the base, and then we go up a few bit sizes to a bigger bit. It is always best to start off smaller then go up in size. One, this reduces the chance of cracking the plastic, and two, you have a guide hole for the large drill bit, stopping it from slipping and drilling off course.
As I used an electric hand drill, the hole was not perfect, but for our purposes, it will do nicely.
Next I checked the fit, with the switch. All looks good so far.
Next: Holier than thou