Markers have been installed on the Main Injector tunnel ceiling indicating were the magnet pole tips should be located. Because the pole tips are enclosed within the flux return of the magnet and the magnetic center varies from magnet to magnet an offset will need to be provided to install the magnets correctly. This offset will appear on the magnet label located on the down stream end ( proton direction) of the magnet. The offset will always be referenced from the label end of the magnet. This offset will indicate the distance the magnet should extend beyond the ceiling marker ( see figure below). By using a carpenter square one should be able to accurately install a magnet in the z direction within 1/16 ".