Hello GMichalski,
this entry mentions a 1971 analysis of Iwamoto's kills which suggests up to 87 WW2 kills:
https://stringfixer.com/ar/List_of_W...ar_II_air_aces
I'll try to locate that...
It must have been a study by by Izawa and Hata:
https://airpowerasia.com/2020/08/16/...e-of-all-time/
Have a good start into the weekend,
Michael