Clincher holders hold a pair of clinchers for bending the legs of a staple driven by a driver, and have slanting guide faces for guiding the tips of the legs of the staple toward the clinchers. The jig further includes at least one scale of one or more markings that represent a cutting angle andor a \u201crise and run\u201d measurement. The openings in the header plates for the modules are flanged and have a thickness of at least about 0.