The end of the cam is threaded. There is a pin that holds the advance unit in place on the end of the cam.
The rod through the cam is hooked to the advance unit by the slotted disc on the end of the rod that engages with the tips of the weights on the advance unit. If you have everything properly installed on the advance side the rod will be timed right.
On the rod there is a pin that lines up the disc on the right and a pin that holds the points cam or Pamco rotor. Both pins must be lined up on the same side of the rod. Look in your repair manual, it tells you about this.
Leo