WARNING: This page is about a different car, the 2006 Infiniti G35. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Exploded View Of Fuel Injector And Fuel Tube Components With Torque Specifications
Courtesy of NISSAN MOTOR CO., U.S.A.
CAUTION:
Do not remove or disassemble parts unless instructed as shown in the figure.