[MTK46]

The duct for my bedroom is visible in the storage area. It is feed by flex tubing coming off the front heater unit. It runs from the rear of my generator compartment to the sliding doors accessing the water tank, gray & black tanks water manifold etc. It's about 2-3" deep and as wide as the bedroom vents. Being so far from the living room vents I don't think if they were tied together you would feel much heat.
We had a Montana back in 01 that had the furnace mounted in the rear living area. Had great heat there but big time lacking in the bedroom up top. Just to far to feel much heat or flow.