Here is the quick and dirty.
My setup is in the back right corner of my garage, butting up against the stair case that is inside the house going up to the Bonus Room.
The Bonus Room sits above the garage, so the right garage wall is the bonus room wall.
To the right of the garage is the dining/family room.
to the right of the bonus room is the AC unit, sitting above the dining/living room.
I need to route an air vent 6" or so, under the floor of the bonus room between the floor joists and then through the ceiling of the garage. My thing is what 2x4's can I cut to route the ducts, and how do I reinforce the cuts and allow room for the duct.
I talked to a guy that will look at it tonight. I am hoping that he will be able to tell me if it can be done or not.