This is a nice informative thread. But the focus should be more on creating awareness to detect accidental JDM imports.
So far what I know about detecting a accidented JDM car includes
i) Missing auction sheet
ii) Missing airbags (how to determine the airbags are missing? Some cars have 2/4/6 or 8 airbags. Do we have a standard e.g. Vitz has only 8 airbags and not less?)
iii) Tempered ODOmeter
iv) Find if front of the car is painted or not