An instrument system for performing spinal surgery that helps provide optimal plate selection as well as an improved temporary alignment and retention means, without the need to penetrate the vertebral bodies with temporary fixation pins. The instrument system of the present invention has a clip that possesses features that temporarily center, align and position the plate to the interbody cage. This clip mates with the cage by hugging the outside parameters of the cage, as well as within the window (central through-hole) of the cervical plate.