There's more than one way to skin this cat, if you run a fuel filter you can pull the fuel line from the tank side of the filter and fuel that way with just a single clunk set up. If you have a fancy, cowled airplane, you can run two clunks and buy a fancy metal plug and metal ferrule assembly (Hangar 9 has a nice kit) to go through the side of the plane or the cowl. Great Planes sells a refueler valve assemble with a special nozzle also, but many are worried about complicating the fuel inlet process with that set up. If you are looking at extreme aerobatics, many pilots feel two clunks may interfer with proper fuel draw once the tank is getting toward the empty side. In that case, you can install a T in the line between the tank and the needle valve. You will need to either pinch the fuel line or close the needle valve to fuel and defuel with this set up. If your not sure. Go to Tower Hobbies, look up one of their Great Planes models similar to yours, then click on the manual and look through instructions and illustrations for other planes, until you find a set up that appeals best to you and your model.