Whirlpool/Kenmore Heater Element Bulb Broken?

The heater/grill element bulb is broken. I bought a new bulb to replace it, but it did not come with instructions on how to replace.
I think I need to take the hood/microwave out and open from top to replace.
This is a newer model microwave with grill/convection oven features.
The cost of repair/service is as much as the microwave itself. We had a Sears Repair guy come by to check our oven (still under warranty). He didn't have a clue how to change the microwave heater bulb.
Has anyone changed one of these bulbs? Microwave model is Kenmore model 72181629600 (made by Whirlpool).