With the fuel filter in place midway in the fuel tank and the remainder of the line sticking out of the tank, cut the fuel line to give you an inch or so of slack for reconnecting to the tank.

Push the other end onto the carburator - the nipple that's closer to the cylinder. You should push it in to closer to the bend - further than my photo shows.

Push the remainder of the fuel line into the outer hole in the gas tank - try to use the old return line to determine the length. I think it should hit the side opposite of the hole.

Cut the fuel line to be submersed in the fuel, have a little slack out of the tank, and connect to the return line (on left in picture) of the carburetor.