It's almost certainly 747 or 77W. The ITM flight is just a tag-on flight for one of the longhaul aircraft to keep it busy during a long rest at NRT.
F seat is only for the Super Seat tickets which is probably why you can select it on Expedia, since it's probably offering you the Super Seat fare. On the ANA website, try searching for "Super Seat Premium" ticket which will also book you into one of these seats.