Dont worry about MBS206 probably some c**ksucker that wanted to become a cop and never made it. Try the following things as you stated, like with the manuals and finding the model for FIDLR unit or what ever they call it. However i wouldn't give up and try your best, make up that you need the car for work. Id still maybe argue the point he wrote 115km/h on the sheet even if he says 146km/h.
The cops in this country are complete idiots cant even do there jobs, you can argue that they do there jobs what ever you want to say but compared to police in my home country there a f****ing joke compare to them. Im sure he would of written off the fine if you gave both cops $500.
Otherwise if during the court case you see you dont have a chance just plead guilty, but as a last resort only. As the thing is the sterotype is also a huge issue, because the Skyline in the police books have a bad name, they stereotype that anyone drives a skyline is a hoon. Thats why skyline owners are most likely the ones that get pulled over the most randomly.
Otherwise id just want to mention good luck in court, but the system seems really f'ed up.