[jetskier]

Since you have a 3791, you can run them down the wall behind the buffet. There are two vent pipes for the bathroom and waste tanks. If you remove the control panel in the upper cabinet with all the switches, you'll see the wall is opened up and the two pipes are there. They run from the basement to the roof along with a ton of the wiring. When you get on the room, you'll see them. This weekend, I used this area to add two more sets of wire to expand my system and used this chase to run them down. I used a 1.5" hole saw and carefully drilled through the 3/8" roof plywood about 4-5 inches laterally away from the two plumbing vents since they line up with the wall below. Make sure to pull the trigger on the drill so you can stop it from spinning as it breaks through. When I pulled the drill, there were a few of the 12g Romex runs (probably for the ACs). I used my fish tape to probe along side and it dropped in the wall cavity right to the open space behind the switches. I pulled the wire to there and then ran the fish tape down to the basement and pull the other end down there.