Normally lounge usage is restricted to the terminal of departure at NRT -- so the ONLY choice is to use the BA lounge. Which no longer exists (unless it has recently been re-opened). BA uses the NW lounge on a contract basis -- so you must be flying BA F or J to access that fine NW lounge. You might want to check further that lounge access is possible in T2 (the arriving terminal), and what arrangements BA has at the time of your travel in T1. I am 99% sure that you will have zero lounge access at NRT based on being WP. Maybe you can arrange with QF for some lounge access, in advance, as I think it will need some special arrangement. Connecting in HKG would have been so much easier -- and you would have had Wing/Pier F lounge access without any fuss; but NRT does not work like that!!!! Overall a rather unfortunate choice of routing, I hope the fare was cheap enough to compensate for it.