This is what goes into building the throw mechanism.

View from the top after installation.
Track View
Starting with a 1/4" X 1/8" brass tube, drill three hole in it. This is an image of the hole for the rod that will actually move the throw bar.
You may need to clean up the hole for the rod to fit in.
Here is the second or "Pivot" hole drilled for the #6 wood screw.
Cut the rod to fit and shape the end to go through the throw bar. Then solder the rod in. Next drill the hole for the throw cable and cut the unit off!
This is the unit mounted with a 1" #6 wood screw and 2 #6 washers.