WARNING: This page is about a different car, the 2011 Infiniti FX50 and 2011 Infiniti FX35. However, it is still accessible from the selected car via links, so may be relevant.
Remove the push-button ignition switch fixing pawl using a remover tool (A), and then remove push-button ignition switch (1).
Fig 1: Removing Push-Button Ignition Switch Fixing Pawl Using Remover Tool