An anterior cervical plating system is disclosed which includes an elongated plate having a pair of bone screw bores at opposite ends of the plate, and with bone screw slot configurations in the middle bridge portion of the plate. A single locking screw is provided at each end of the plate which engages the heads of the bone screws trapped within recesses of the plate. The locking screw provides a rigid fixation of the screws to the plate, while the heads of the screws are flush or recessed below the upper surface of the plate. The invention further contemplates a drill and tap guide assembly which can be mounted on the fixation plate to provide a firm foundation for accurately drilling and tapping screw holes into the vertebra to be instrumented. The drill and tap guide assembly includes an assembly support which is engaged to the plate by way of a positioning screw and cross pins mounting the positioning screw to the guide body. A tap sleeve and drill guide can then be supported by the assembly support, which both thereby provide accurate positioning for a drill.