Unplug the range power cable, and open the oven door. Notice the glass top mounting screws on the underside of the range corners.
Remove the mounting screws with your Phillips screwdriver.
Lift the glass cooktop up, and unplug the wiring harnesses connected at the underside of the cooktop.
Remove the screws holding the metal heating elements in place, and pop the clips at the sides of the elements.
Move the heating elements to your new cooktop. Replace the screws and secure the clips.
Plug the range wiring harnesses into the ports on the underside of the new cooktop.
Place the cooktop over the range, and secure the mounting screws.