Abstract: A fuel filler neck assembly having a uniform hemmed connection between an outer funnel portion and an inner funnel portion. The outer funnel portion is typically defined by an offset-expanded cylinder and sidewalls of varying thickness. The inner funnel portion includes sidewalls that have an internal thread, which is configured to mate with the threads of a gas cap. A hemmed connection is used to join one end of the outer funnel portion to one end of the inner funnel portion. The sidewalls at one end of the outer funnel portion are folded or bent inwardly and around the rim portion to define a curled portion. A tooling assembly for producing a uniform hemmed connection between one end of the outer funnel portion and one end of the inner funnel portion. A method of producing a uniform hemmed connection between portions of a fuel filler neck.