Assuming you need to remove the fuel pickup tube from a plastic gas tank:
First, you will need to remove the gas cap. Once the gas cap is off, insert a small diameter hose into the tank and place the other end of the hose into a gas can. This will allow the gas to siphon out of the tank. Next, locate the fuel pickup tube. The fuel pickup tube is typically located near the bottom of the tank and is attached to the fuel pump. Once you have located the fuel pickup tube, disconnect it from the fuel pump. Finally, remove the fuel pickup tube from the tank.