If the ceiling is tall enough, it's not too difficult or expensive to raise the height of the opening and mount the opener higher. For a straight-forward solution: some kind of LVL beam to take the place of the likely solid wood sandwich header. That would take 3-4" off the opening height while having the same strength for the span. More invasive door surgery could result in the opening being nearly level with the ceiling. Don't know how you'd tackle the door/opener then. I'd just have swinging barn doors.