Instruments, kits, and methods are disclosed for installing an implant spacer through an incision and down a surgical corridor. The instruments also serve to align a drill guide and align and insert a spacer stabilizer for stabilization of adjacent bone portions. The instrument comprises an elongated guide bar body, an inserter face at a distal end of said guide bar body for abutting an instrument attachment portion of a spacer, a connection tip portion for securing a spacer against an inserter face, and a guide portion of said elongated guide bar body for aligning instruments with said spacer and for introducing a stabilizer to secure the spacer in a predetermined position between the bone portions. Included is a retractable graft block for securing graft material within an aperture of said spacer during insertion of the spacer.