Here's a link to an old thread a few months back when HalWade and I built one for a T100. It came out pretty cool and was a low tech jig set up. (The funny looking photo in the upper left.) It was our first one, so not like this is the standard by any means, but will give you something to look at.
In the end for the bolt on bottom part I used a long, grade 8 shoulder bolt instead of the stupid allthread idea.