optical endstop mount and adjustable target

First of all this is my first posted 'thing'. When I made it I wasn't thinking of posting it, so sorry there aren't any pics of the parts not assembled or of the assembly process.

I used a brass 3mm threaded insert in the target piece pushed in with a soldering iron, but you could probably just as well thread the screw directly into the plastic. The screw itself passes through the top, with a washer under the head, another washer, then a fiber lock nut. Tighten the nut until there is no slop