An upright space-dividing wall panel is provided having an internal frame and a top cap attached to a top rail of the frame. The top cap includes a lengthwise channel in which threaded fasteners are slidably received for engaging the top cap to the frame rail. The top cap further includes side channels which cooperate with coupling brackets for securing a second panel to the wall panel. Further, a locator clip arrangement is provided between the top cap and a side trim cover on the end of the wall panel for precisely locating the trim cover relative to the top cap.