How do you replace the fuse in a sharp microwave?

The light bulb is inside the metal body of the oven. You'd have to unscrew the cover and remove it to get at the light bulb. It's tricky, but doable for the patient, mechanically inclined do-it-yourselfer. The difficult part is getting the cover back on the unit. Many of these ovens have no screws around the front of the cover; they rely on the meeting point of the cover and front trim to slide into one another. The edges can be sharp and can cut. Don't forget to unplug the thing before diving in.