Caliper Bed leveling holder for Geeetech I3

Looking for a way of using a cheap electronic caliper to level the bed on my DIY I3 pro b, I came across a "thing" that needed to be screwed onto the extruder carrier, and was hard to use. I had seen the sort that used a "clock" measurer hooked onto the smooth bars. So I worked out a way of using the same method.

The Caliper is simply held onto the "thing" with elastic hair bands as in the photo. There is a lump on the back of my caliper that sets how low it goes into the slot for it in the