A computer model is formed of a mounting component (18) to be mounted at a target location on a mounting surface (12) of a base component (11). A position and viewing direction of a digital camera (3) is determined relative to the base component (11) and a live image (11′) of the base component as viewed by the camera (3) is displayed on a monitor (4). The monitor (4) also displays a mounting component target image (18″) generated by a computer (2) of the mounting component (18) mounted at the target location on the mounting surface (12) superimposed over the live image (11′) of the base component. A user physically moves the mounting component (18) relative to the base component (11) until a live image of the mounting component as viewed by the camera (3) coincides with the mounting component target image (18″).