Sorry it took me a while to respond. Here are some pics displaying my wall as it is currently. The first pic is of the theater side with the return opening NE of the tank. The second picture is just on the other side of the same spot.:
Using this dead vent design from Ted:
Instead the Supply and Return on the theater side will be at the top and exit on the bottom on the adjacent side. I had to put the drywall on the inside of the exterior wall of the theater as that wall was already there and drywall could not be placed on the outside of that wall. There is a new wall built in front of that wall if that makes sense.
I have 6" PVC that will go through the double wall and then 6" flex duct attached to that. Just need to know how best to start it with the boot and all and if it would be best to drywall up the theater side wall THEN cut out the hole for the boot and 6" PVC.