A locating device for locating the centerpoint of a body such as a recessed light fixture behind a ceiling. The device includes an extendable first member connectable in the center of the body and a second member positionable on the outer surface of the ceiling. A magnet positioned in the first member cooperates with a magnet positioned in the second member to maintain the second member in an aligned position with the center of the body. The extendable first member accommodates various size bodies so that the magnet positioned in the first member extends to the ceiling for attraction to the magnet positioned in the second member.