Wagon Model

Disconnect the ground cable from battery.
Remove the clip.

Fig 1: Locating Clips
Courtesy of SUBARU OF AMERICA, INC.
While pressing the section (A), insert your finger or a flat-tip screwdriver wrapped with tape into the clearance (B) to remove claws in the order of (C), (D), (E), and remove the rear combination cover.

Fig 2: Identifying Section And Claws Of Rear Combination Cover
Courtesy of SUBARU OF AMERICA, INC.
Remove the two bolts, and then detach the rear combination light by pulling it to the rear side of vehicle.

Fig 3: Locating Rear Combination Light Bolts
Courtesy of SUBARU OF AMERICA, INC.
After turning the sockets of the tail/stop light bulbs and rear turn signal light bulbs, remove the rear combination light.