So you are converting your Ender 3 to a sensorless endstop setup?
You can replace the switch with this much sturdier part.
Fits the original mount on the Y axis.
Perfect boring from the start.
If you use Cura, use a 0.4mm nozzle, In Quality set the Wall Line Width to 0.5mm, set the wall thickness to be a multiple of 0.5mm (e.g. 2.0mm), and the Wall Line Count to be equal to the thickness divided by 0.5mm (e.g. 4 wall lines for 2.0mm thickness).
If you use Slic3r, Print Settings > Advanced > External Perimeters = 0.5mm.