>>64505755
Nevermind, just saw >>64505724
>>64505766
You are stuck with one of the most boring military eras for Japan. Japan wasn't even in the territory of getting US surplus vehicles until 1950 and their domestic developments didn't take off until the mid 1950s. You are stuck with the Godzilla -1 approach of using Japanese surplus and late war prototypes. The interesting routes you can go is stuff like the O-I (If this is a real production you will have to get in contact with FineMolds because I think they own a lot of the O-I documentation and media rights). There is the Chi-Ri, Type 5 Ka-To. These are all scrapped prototypes, but within reason of being built in your scenario.