There have been a lot of stories over the years and I know there was a police option code. I am also aware of a few departments that had undercover GNs and Ts, but what is the final concensus or proof of FBI GNXs (I doubt it) or fleet type GNs for the FBI as in this article? My understanding is that there was never anything special from Buick directly, just whatever the department or agency did to the car. This article claims it was marked GN and numbered for the FBI. I am also aware of the 145 mph speedometer, but I have never thought it was available from the factory, just aftermarket. Thanks