Mounting a GE microwave oven into a cabinet requires a mounting kit sold by GE that is designed for the model. Not all GE countertop microwave ovens can be mounted in a cabinet, so it is important to make sure that a given microwave has a compatible trim kit.
In addition to built-in cabinet mounting and trim kits, GE sells a mounting kit for attaching a microwave to the bottom of existing cabinets. Though this kit is not model-specific, only certain models are compatible with the mounting kit. Attempting to mount a microwave not intended for such use may damage the microwave or cabinets.