Sorry about the confusion.
If you look at the unit trays, you may notice that each slot for a figure stand has a little round knob in the back. One of those slots will have the round knob on the opposite side as the others. That slot is for the commander (if the unit has one). The other models in the unit won't fit properly into the commander slot because of the little round knob. That should make it easier to remember how many models go into each unit.
Hope that helps!
Thank you - the only confusion was the one I created .
Most everything is right there in the rules but some of the finer details just need a 2nd read for me to catch.
I tend to learn rules quicker with more situational examples written in. I believe the rulebook was written well, I just need to look a little closer . Thanks.