Subaru Legacy 2004 Service Manual page 3334

Steering Gearbox [RHD Model]
POWER ASSISTED SYSTEM (POWER STEERING)
3) If the steering wheel spokes are not horizontal
when wheels are set in the straight ahead position,
or error is more than 5! on the periphery of steering
wheel, correctly re-install the steering wheel.
(1)
PS-00513
(1) Within 5!
4) If the steering wheel spokes are not horizontal
with vehicle set in the straight ahead position after
this adjustment, correct it by turning the right and
left tie-rods in the opposite direction each other by
the same angle.
PS-64