Replacing the cooktop glass takes about 20 minutes and the only tool needed is a 1/4" nut driver. Best with an impact driver or drill, because you'll be "tapping" the holes in the sheetmetal of the new top.
1. Pull out the unit from the cabinet. Disconnect the Power, or turn off the circuit breaker.
2. remove 3 1/4" sheetmetal screws from each side, about an inch below the glass
3. remove 2 more from the back.
4. carefully lift the front up enough to disconnect the wire harness for burners on left and right
5. Turn over the glass and remove the screws holding the burners in place. There are 2 for each burner.
6. Transfer the 4 burners and wire harness to the replacement top (easier with a helper)
7. Replace all the screws, replace the top, reconnect the wire harness and put all the screws back in place.