The rear bumper is actually super, super easy to remove. It has a maybe 6-8 clips and a handful of bolts. You can pull it off in <10 minutes, although a helper is suggested to avoid scratching it.
But it might be possible to install it without removing the rear bumper. The little insert above the hitch (in the Bell Lexus photo) should pop out by itself.
But it might be possible to install it without removing the rear bumper. The little insert above the hitch (in the Bell Lexus photo) should pop out by itself.