You have to finishing Gold medals for Stage destroyed time, medals collected, and enemy targets destroyed. Virtually impossible to do when going for a record high score.
I have this inp on my old desktop. I am not sure if it is still working, but I can check if I can retrieve data from the disk. Besides this I also have a inp for BF109 which finishes 1st loop with 1.18m
I don't know if you are aware but Striker's 1945 is available on Google play via Mobrix. Much harder to trigger bonus train because of autofire but the difficulty is very close to the arcade on Very Hard difficulty.
What do you mean by reference score? As impressive as this high score is, it has been beaten in Japan using P-38 lightning and Zero fighter. Technically P-51 is the best plane for record scoring