An instrument for preparing a surface of a vertebra, such as a vertebral endplate, for receipt of a spinal disc implant. The instrument includes a working tool with implements on one or more surfaces of the working tool that act on the vertebral surface. The instrument includes a rotary-to-linear translation system to cause the working tool to move; for example, from side-to-side, top-to-bottom, or along a path that includes side-to-side and top-to-bottom aspects. The rotary-to-linear translation system may include a drive shaft having a cam pin at a distal end, and a cam follower slot at an anterior end of the working tool.