A process for utilizing a spinal implant guide made using a diagnostic imaging tool to facilitate implantation of a device in the spine. The spinal implant guide preferably has a body designed to conform to certain predetermined, patient-specific anatomical vertebral landmarks. The guide may be fitted to the anatomical vertebral landmarks pre-operatively and/or during a surgical procedure using 3-point fixation technique to thereby substantially demarcate an optimal alignment, trajectory and angulation for the spinal implant device.