Mount for filament runout sensor on Ender 3 V3 SE, that can be used with

Spine Cable Chain: https://www.printables.com/cs/model/695436-ender-3-v3-se-spine-cable-chain/files

and Clamp for it: https://www.printables.com/cs/model/754271-ender-3-v3-se-spine-cable-clamp-to-spine

Filament Sensor I have used: https://www.aliexpress.com/item/32796458815.html?spm=a2g0o.order_list.order_list_main.40.67c2586aprDg3E&gatewayAdapt=glo2isr

I have used M3*L5*D4 insert in upper screw hole for sensor and and 2x M3x20 and 1x M3x30 flathead screw.

Print settings are up to you, but I recommend 0.2 layer height and at least 4 walls.