I guess the blind-spot-light has black plastic i.e. light-absorbing, behind it. I am thinking of painting the plastic behind the light white to make the monitor brighter.
Has anyone seen the actual light itself and behind it, e.g. when the glass mirror became unstuck from the black plastic part & fell off? If you have, do you think it feasible to whiten behind the light? I wouldn't detach the glass from the plastic but would open up the plastic just behind the light for access
BTW I have whitened the black plastic behind the CABIN light (up by the rear-view mirror) & it worked well.