Knee Dart dimensions, Diameters? (for machining)

I'm going to be machining up a set or two of these knee darts for a buddy and I have some questions:

1. what is the preferred method of attaching these to the knee armor? A threaded screw hole in the back?

2. I need the diameters, and measurments of them so I can machine to accurate specs? Any one got this on hand to share?

3. is there a difference between ESB and ROTJ? I'm not a OT Fett expert, I'm more interested in Jango and that is where I've done my research..

Badger

No Body has these? I have another fella looking for dimensions. if any one has these that would be great.

sorry Badger, I keep meaning to measure my knee darts, but I keep forgetting. I gotta put it on the list of things to do!