Abstract: An intervertebral milling instrument for removing calcified fibrous cartilage (CFC) from adjacent vertebrae during spinal fusion or spacer implantation surgery. The milling instrument includes a grinding wheel carried within a guide housing sized to fit closely into the intervertebral space, and to expose the grinding wheel on opposite sides thereof for controlled removal of CFC layers from adjacent cortical end plates. The grinding wheel is rotatably driven as by attachment to a surgical drill, preferably to include saline supply to and suction removal from the grinding site. The controlled removal of CFC layers is limited to about 100 to about 250 microns, thereby avoiding exposing the cortical end plates without excessive bone removal. The instrument is conveniently provided in a kit having multiple guide housings and associated grinding wheels of different sizes to fit into different intervertebral spaces.