Sorry for the late response on this one. I've built two .60 sized Tower Hobbies kaos with retracts. The easiest way to handle the tank situation is to install the tank on the CG. You need to move the radio gear around a little bit it ends up being a very simple way to go. I've powered mine with a Magnum .60 and it has plenty of draw with muffler pressure to move the plane through any manuevers that I'm interested in doing. Simple, easy access to the tank, simple way to make all the different systems work.

Rick