If I recall correctly it's the same size arm rest. A door in the arm rests between the two seats flips open and the screen comes up and is swiveled for viewing. You must be on the evening flight (9:15pm) out of LAX. The afternoon flight (3:45pm) switched to the A380 about a year ago. If it's possible for you I would suggest switching to the A380. I've logged 20+ flights on the 777 and 6 on the 380. The 380 is a much better flying experience in my opinion.