How to create a story and half roof with 2 story gable addition

[DJohnsonSC]

I am trying to create a story and a half main house that has a two story gable roof addition.  I have been able to create the story and a half with a 1 story addition but can't figure out how to add a second story to the addition.  The main part of the house has a 10/12 roof (created by build roof options: move roof up 12', ignore 2nd floor).  The goal is to have the main roof 10/12 and the 2 story addition a 6/12 gable.

Pics below are a quick mockup. One showing the successful story and a half w addition.  The other a bit more unusual configuration that I may not be able to get past the building inspector.

Thanks in advance for any help provided.