I think I figured it out! I took out the back seat coolers so i could have access to the sides of the boat. I put a 350lb sac on each side with the fill/empty spout coming out of the cup holders on the floor behind the driver and passenger seats. Then put everything back to normal except the cup holder. Ill try to post some pics later. really easy project for a better wake without taking away from seating or floor/storage room.
I was looking at doing the same thing with my 2009 challenger 180 as I do not want to compromise my seating/floorspace. What are the dimensions on your side sacs? When you fill them they don't interfere with the tubing from the bilge pump or the tubing for the gas intake? I have stainless steel cup holders and they don't seem to come out to run the fill/empty spout through them. Any help you could offer would be greatly appreciated. I just bought a Ronix Koal wakesurf board and I can't wait to use it!