Extruder Pointer / Indicator for Thing-O-Matic MK6

This is a pointer or indicator for the Thing-O-Matic MK6 Stepstruder to show when the extruder motor is actually turning. I find it very helpful to know if/when the extruder motor is skipping steps and the easiest way is to watch the shaft rotation (or feel the filament feeding with your hand). But the MK6 shaft end is flush with the support bearing, so there was no easy way to mount any kind of flag/indicator. Up until now, I just used a piece of blue tape.

I figuired that I could use a