Subaru S209 2019 Service Manual page 215

(3) Make a mark-off line (c) according to pattern papers (a) and (b).
(a) Pattern paper LH OUT
(4) Cut the lower part of the bumper face - rear along the mark-off line.
CAUTION:
Remove any burrs on the cut sections (a) to avoid damaging the vehicle.
2) Perform the work for installing the rear quarter spoiler.
Rear Bumper
(c)
(a)
(b) Pattern paper LH IN
(a)
EI-27
EXTERIOR/INTERIOR TRIM
(b)
(c) Mark-off line
(a)
AA-10154
AA-10064