I actually just did a trip to Australia from uk with both legs via Tokyo.
Make sure you get a basinett, and if possible make sure its a basinette in the centre aisle and not one by the windows. I flew with JAL and their was more leg room, also it was easier for both me and my partner to get out and go to the toilet, with the window seat, the basinette pretty much locks you in unless you go climbing all the seats. Also, very NB, the arm rests by the window seats DO NOT lift up, where as the aisles seats arm rests do so you can lift them up and get yourself more comfortable by sitting at an angle or putting your legs all over your husband
To be honest, i found reversing my LO sleep patterns easy, it was changing the feeding patterns that i find difficult (No good trying to get them to sleep through the night if they are going to keep waking up for food) So for this, during a normal day my LO gets 4 bottles every 4 hours but on the plane, if the flight is during the day, instead of feeding him every four hours i wait till he's really hungry (normally longer than 4 hours) and i only feed him as much as he need to keep him happy. By holding back on the calories during the day, i was able to make him more hungry at night (which is actually your daytime,,,, hope this makes sense!!) And the when i arrived at my destination i stuck to the feeding every 4 hours during the day. I know this sounds terrible but you basically have try your hardest to get at least some food into them so that you can start add ounces during the day and hence take those away during the night. This will also mean waking them up to feed and keeping them up as much as possible even though all they want to do is sleep. It might feel like hell the first day, but the first day will be your hardest, it'll only get better. It took my LO about 3 days to get back to sleeping through the night.
Also, (last tip, i promise) flying can be very dehydrating so make sure you give your LO plently of water, not only will this quench the thirst but it'll also fill the tummy up for a little while which will help when swapping feeds around