How do I approximate head position?

You can approximate the head position using a Head Binding object. To create a new Head Binding object:

Click on Add New > Head Binding in the Objects panel
Set its Attach To Point to Forehead, and make sure Face Index is set to 0.
Remove the Face Occluder child since you won't need it.
Add a new child to the Head Binding object, name it something like "Head Top"
Position the Head Top object to the approximate top of the head. We utilize the local position (0, 2.4, -9.0) but you can adjust as needed.