A spacer shim for locating between adjacent ground engaging tools of a work implement for an earth working machine includes a shim body, a shim upper protrusion, and a shim retention surface. The shim body includes a shim first leg and a shim second leg spaced apart to form a shim slot for receiving a lip of the work implement. The shim upper protrusion extends from the shim body and is adjacent to the shim first leg. The shim retention surface extends between the forward end and the shim upper protrusion and is configured to contact a bottom surface of a portion of an adjacent ground engaging tool.