Ender 3 Filament Runout Sensor

I loved the idea of reusing the Z-Stop I had available after installing the BL-Touch. However, I didn't really like having the sensor just hanging off the filament. I remodeled the parent design from @The_Goss to mount securely to the Z-Stepper mount.

All the instructions and examples from his model still apply, then just slide this into place over the Z-axis roller spindle.

v2 - Complete mount
v1.3 - Sensor tray only for remixing into other mounts/parts

***Updated 2/7/19***
1. Adde