The self-consistent-field (SCF) theory developed in Part I [J. Chem. Phys. 116, 7283 (2002), preceding paper] is employed to compute the interaction between particles coated by end-grafted homopolymers in good solvent, where the particles and the homopolymers have comparable sizes. The result shows that, contrary to the prediction of the conventional theory for colloidal stabilization and previous SCF studies, the interaction is attractive, repulsive, and attractive at large, intermediate, and small distances, respectively, for densely grafted particles, while it is purely attractive for sparsely grafted particles. The attractive interaction is a consequence of two important factors that were ignored in previous studies: (i) the sphere-sphere geometry of the system and (ii) the segment density associated with individual particle being deformed anisotropically, with respect to the particle, under the perturbation of other particles. We argue that the conventional wisdom that end-grafted homopolymers in good solvent always impart stability indeed is correct only in a kinetic sense and that our result will become more observable in systems composed of nanoparticles. Limitations of our prediction and considerations that must be carefully taken into account when generalizing our result to micron-sized particles and star polymers are discussed.