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. An inserter instrument comprises an elongated guide bar body having a guide portion for aligning instruments with said spacer and for introducing a stabilizer to secure the spacer in a predetermined position between the bone portions. In preferred embodiments a stabilizer implant portion comprising a base wall separated by a retaining member by a web wall is introduced into a pre-bored hole in a bone and secured with a stabilizer anchor extending through a central bore. Included is a retractable graft block for securing graft material within an aperture of a spacer during insertion of the spacer.
