Yeah, I'm sure you did exactly that, big guy. Just walked into a dealership, told them you wanted a RHD drive one imported from japan for around the same price it would be for a USDM one and they did all of that for you, right?
You're a moron and your story is a lie, because you didn't go into details, so obviously nobody is going to believe you. Rule number one of internet dick-swinging is that you don't wait for people to ask you to back up your story, you put it all out on the table right then or you've lost all credibility.
Now go ahead and say something only a douche would say like "I know it happened and I don't need to prove anything to you." It will only make your story seem more fake.
Either that, or cough up names of people, the dealership, their process on how they did it, how you got the car registered, what the VIN number was, who you sold it to and pictures of the whole thing, or it didn't happen.