I tried the one this is based on. The idea was solid, but it did not fit my dial indicator it also had a lot of sideways mobility. This version should hold the indicator much more solidly.

I used the amazon gauge http://www.amazon.com/gp/product/B000NPPBVK/ref=as_li_tf_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=B000NPPBVK&linkCode=as2&tag=stuff05e-20 because harbor freight was out of them. I don't know if this also fits the harbor freight one - http://www.harborfreight.com/1-inch-travel-machinists-dial-indicator-623.html.