WARNING: This page is about a different car, the 2004 Nissan Maxima. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Preferred Method Of Evacuating System and Charging Refrigerant
Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 2: Discharging, Evacuating System and Charging Refrigerant Flow Chart