I was in 11K in the second J cabin coming back from ANU on sunday, and with the screen up you are completely isolated from the rest of the cabin. Its not quite as good as 62K though as the bulkhead is right in front of you, so its even more like a cabin.

I did feel completely hidden though - and apparently so did the crew as they didn't bother to offer me a welcome on board drink or a hot drink after dinner.