The present invention is a modular system for mounting lighting and signage. Mount components are attached to gutters by engaging the securing protuberance of the mount component with the gutter which creates tension between the gutter and the mount component. Rail components are assembled to the desired length using connector components and lights or signage are attached to a rail component using hooks. An insertion member is placed at each end of the assembled rail and the rail is guided through an opening in the mount component securing the lights or signage to the building.