[Daryles]

When I swapped mine out I used leveling blocks on the cooktop to ease the MW down on to before lifting it out of the way. As you loosen the screws mounting it to the bottom of the shelf it will settle down on the blocks.
Find a neighbor kid to help.
The fun part is fitting the new one. Putting it in and out a few times making sure the vent in the back fits. I had to cut the vent opening a bit and remove the top row of backsplash tiles to make it fit.