Do-It-Yourself Story

The original knob had an indexing spline at the OFF (top) position of the knob. The replacement knob had the indexing spline at bottom of the knob. The knob would not slide onto the shaft of the switch. A close inspection of the shaft of the switch revealed a flat spring in the groove into which the spline would slide. This spring appeared to be preventing the knob from sliding onto the shaft. Initially I tried moving the spring to the bottom of the shaft, but the knob would not slide onto the shaft. Removing the spring from the shaft allowed the knob to be fully seated on the shaft of the switch.