Abstract: A guide tool for performing a work function step such as cutting or drawing a line along a workpiece including a guide plate having planar opposite sides, a longitudinal slot, a first straight guide edge substantially parallel with the slot, guide flanges along opposite sides of the slot defining a guide channel on a first side of the guide plate, and two clamps adapted for assembly with guide plate, the clamps having a first jaw including a guide member slidable along the guide plate channel and a second jaw extendable through the guide plate slot and a pressure plate for securing the clamps to a workpiece along opposite sides of the workpiece, and clamp handles formed integral with the jaws and spring biased apart to urge the jaws together for clamping the guide plate to the workpiece, and the clamp handles being positioned in spaced relation from the first side of the guide plate for ready access by a user from the first side of the guide plate when the clamps are assembled with the guide plate and the gui