Abstract: An assembly cell for accurate placement of stringer clips in a channel of a stringer for a compound contour section of an airplane fuselage, and for holding the clips at a predetermined orientation while drilling holes for fastening the clips in the stringers includes a fixture having locating surfaces for holding the stringer in a configuration that is the same as the configuration it will have when installed at its designated position in the airplane. The fixture has headers adjustable to conform to the shape of the airplane in which the stringers will be installed, The headers have clamps for securing the stringers against accurately machined reference surfaces on the headers. An end effector is held by a machine tool in the assembly cell for gripping a stringer clip and inserting it into the stringer channel.