X2 on Gooiebob. I have the Flagstaff clone of your Rockwood. Definitely have to pull the AC frame down on the inside and remove the stryofoam blocking the ducting. It was the same in ours. Also check the last vents in the BR and LR. They use that sprayfoam in the factory to close the duct at the end, but they don't do a real great job. You'll have to clean that up as well. Have fun with it. We love ours. DW and I can't wait till the fall when we can turn our inside fireplace on again.
2016 Flagstaff 27RLWS Emerald Ed.
2014 Chevy Silverado LT w/ 5.3
Reese 12,000lb hitch w/ Dual Cam Sway Control