Align the pin on the Single slice with the matching pocket on the Middle slice. Install the desired amount of #2-28 screws to hold the pulley slices together. Be sure to tighten the screws fully. There should be no gap between the pulleys when they are assembled.
For the double pulleys, the screws will need to come from the inside of the pulley stack into the Single slice. For the final slice, the screw goes from the Single slice into the Double slice. This can be seen in the image below.
Screws can be omitted if used with the 7/8” long VersaRoller insert or the slices are constrained by collars or snap rings.
A piece of 1/2" OD Hex can be used to line up the parts during assembly.