WARNING: This page is about a different car, the 2012 Subaru Forester. However, it is still accessible from the selected car via links, so may be relevant.
Install in the reverse order of removal.
Tightening torque:
7.35 N.m (0.7 kgf-m, 5.4 ft-lb)
Fig 1: Locating Fuel Tank Pressure Sensor Mounting Bolt
Courtesy of SUBARU OF AMERICA, INC.
Fig 2: Locating Fuel Tank Pressure Sensor Mounting Bolt