Ballast help with 2008 SANTE

Hey everyone. I am trying to piggyback an older style fat sac with the screw on caps, into my 08 SANTE. I guess that would be the waterbed fittings... If anyone has tried to do this on this particular model, I would just like to know what fittings to use (from Fly High) or if I can pick up all I need from Lowe's and what size hoses I have now. I am thinking, judging by the size of the hoses that I am going to have to reduce down to get them to adapt to the size of the fitting on the fat sac. I have used search and just can't find exactly what I need and I haven't had a chance to look at everything under there yet because I still need to move my sub to the observer's seat. I know you move the overflow from the factory tank to the inlet in the sac, and then run a hose back into the overflow hose that I spliced into. Thanks for any help that anyone can give me.