Some additional notes:
Each Pulley is actually a pair of pulleys, stacked. I refer to these as “Top” and “Bottom” in the above threading sequence.
The “Anchor” is a hole drilled in the cross bar.
Note as you follow the threading sequence, that the the thread always proceeds counter-clockwise around the pulleys (if starting from the drum).
It helps to put a weight on the end of the boom when doing this, to keep the slack out of the thread.
I hope this helps!