A device for applying an adhesive-backed elongated seal (e.g., a weatherstrip seal) to a surface of a substrate. The device comprises a release liner removal tool having a stripper portion. The stripper portion comprises a spacer and a release liner guide surface. The spacer has a leading edge, an angled trailing edge, a central axis and a thickness profile that separates the adhesive on the back of the seal from the substrate surface while allowing the body of the seal to contact the substrate surface, when the stripper portion is positioned between the seal and the surface. The angled trailing edge has a transverse radius of curvature allowing the release liner to be removed from the adhesive, bent-backwards-over the trailing edge, and pulled-off along a portion of the guide surface, while the seal is adhered along its length to the surface.