Limit switch mounts for Shapeoko

I'm in the process of adding limit switches to my Shapeoko. Limit switches are nice because they give you two things:

1) They give you some added protection against driving a carriage off the end of your machine.
2) They give you the ability to set up an auto-homing routine. Auto-homing can be very helpful when you're doing a lot of repeat cutting against a fixed jig.

I found this [5-Pack of limit switches on Amazon](http://www.amazon.com/gp/product/B00DN7Z67E/ref=as_li_ss_tl?ie=UTF8&camp=1789&creative=390957&creativeASIN=B00DN7Z67E&linkCode=as2&tag=zorlackcom-20) for less than $5. That provides more than enough limit switches to set up an auto-zeroing system.

The mounts nestle inside the makerslide. The two holes should be tapped for M5 screws and bolted to the end-plates. [This document](https://github.com/grbl/grbl/wiki/Connecting-Grbl) describes how to connect limit switches to grbl.

[Here's a video of the switches in action!](https://www.youtube.com/watch?v=_koJUzzS