Are you sure you have to cut the tank apart to get it out?
My X2 is a very similar layout and it looks like one could just remove the aft ballast tanks without too much trouble. KGB tank totally different story.
If you did both sides, IMO you'd be increasing the value of the boat with factory ballas operation and waaaay more plumbed in ballast.
Maybe search wake world too. I'm sure someone has removed the factory rear tanks in favor of bags.
'06 X2 MCX
"I understand why some people may not want to do this the way I have recommended but I can't understand the death grip some people have on a toilet plunger with a hose fitting." -JimN