So I was reading the FAQ and the Skaven Rule book, and I think I have managed to confuse myself, so thanks in advance for whoever can put me on the right track.

For some reason that I can't find despite a very clear reading of the Book and FAQ I have it stuck in my head that "Rat Ogres must be placed into the front rank" is a rule somewhere.

I can't seem to find it, but I am just wanting to make sure that I could if I wanted to take a unit of 6 Rat Ogres and 3 Packmasters and make the unit 3 by 3.

Would the third rank (of only 3 Packmasters) count for Strength in Numbers?

I know that if I include a master molder then it must be placed in the front rank. If for some reason I included a master molder could I still make the unit 3 by 3? would it have to be 4 by 3 with an incomplete last rank?

Thanks in advance.