I'm not sure how you would duct it, but my BG10.4E has a duct up there and it is a nice addition if you can figure it out. My 9.6 did not have one, like yours. Another thing I wanted to do on the 9.6 is put a small duct into the bathroom. That looked quite doable.
Bigfoot 10.4E, 2015 F350 6.7L DRW 2WD, Autoflex Ultra Air Ride rear suspension, Hellwig Bigwig sway bars front and rear