;FIG. 8a is a cross-sectional perspective view of the bone screw of FIGS. 1-3 positioned for assembly within the coupling member of FIGS. 1 and 2, including a desired directional force for assembly, and FIG. 8b is a cross-sectional perspective view of the assembly after the bone screw has been inserted into the coupling member; andFIGS. 9a and 9b are a perspective view and a front view, respective