I remixed the Filament sensor bracket for CR-10 from GiantMidgt so I could use the same sensor after upgrading to a bondtech extruder mounted in bowden.

Just replace the printed part in the e3d adapter on the bondtech by this one.
You can find the lid and the instructions for mounting/connecting the sensor in the original design page.
(You may have to re-drill the hole at 2mm depending on your printer.)

Update:

• I've added a longer and cutted version for assembly where the z-rod is really near the extruder (like on cr-10 or ender-3 printers)