We shut off the breaker to the stove, pulled it out and removed the five screws on the upper back.
Then we pulled off the knob and removed the two retaining screws that held the regulator in place.
Then we located the regulator and replaced it with the new one making sure to connect the wires to the same terminals before we took the old one out. Then we put the two screws back which hold the regulator in place. Then we replaced the knob and turned the breaker back on. Total time was ten minutes. Works fine now.