Basically you will need to slide the microwave out of the oven shell to gain access to the top side of the microwave, then it's a simple swap. To do this, you will need to remove the side rails * screws, pull the entire oven forward. Remove 2 screws holding the control panel at the top and remove both the plastics vents above and below the microwave. The remove 4 screws, 2 on each side that hold the microwave to the shell. Next you need to pull the microwave forward from the shell like in the picture part way out. Mine was tight and took more force than I expected so I was not sure if I got all the screws or not. It was eventually persuaded. Make sure the power is switched off and don't pull the entire oven on top of you. Have fun.
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Basically you will need to slide the microwave out of the oven shell to gain access to the top side of the microwave, then it's a simple swap. To do this, you will need to remove the side rails * screws, pull the entire oven forward. Remove 2 screws holding the control panel at the top and remove both the plastics vents above and below the microwave. The remove 4 screws, 2 on each side that hold the microwave to the shell. Next you need to pull the microwave forward from the shell like in the picture part way out. Mine was tight and took more force than I expected so I was not sure if I got all the screws or not. It was eventually persuaded. Make sure the power is switched off and don't pull the entire oven on top of you. Have fun.