Jetpack, I copied and zoomed the drawing and you have top and side view. if the drawing is fullsize (seems to be) then you can get most dimensions needed with the only one missing that was obvious was the torque wire length. The units I have personally seen were brass tube and piano wire soldered together. I would think that there is a small ball thrust bearing for the TQ wire to spin against since you would want to eliminate as much friction as possible but cannot say for sure. Give it a try, you can probably come up with a close enough copy.