I would probably shop weld the gusset to the beam, bolt to the column using double angles. If this is already in the field, while you could bolt, drilling the holes in already-installed members is far more trouble and expense than welding. Just be sure the welds take all of the load so you haven't mixed bolts and welds on the same plane of movement (most easily accomplished by welding the angles that are already bolted.)
See AISC 13th Ed page 13-6 for an illustration. (or in the LRFD 3rd Ed. on page 13-7] If you are designing steel, you need the AISC Steel Construction Manual. Generally, I don't separate connections for shear and lateral, since they have to act in concert.