Answer Hello. To install a new light bulb in the microwave you will have to unmount the unit from the wall. You should have access to the hold down spring part #20 in diagram W10465869. Here is the link to the diagram: http://www.appliancepartspros.com/sect/o/4/l/o4lgm1o6y6.gif . Hope this helps! Read More... Answered by AppliancePartsPros.com | Thursday, April 21, 2011