A mate was about to buy a 33 GTR, the thing was mint and had a bit of work done with all top shelf items. He noticed that the VIN # appeared to be tampered. When i say "appeared" i mean there was no effort in masking the change. It looked like someone got the Dremal tool and engraved the second half of the number, free hand, over the original digits (you couldn't make out the original #s). After ringing DOTORS/RAWS, Vicroads, Police, importers, etc. He couldn't get a clear answer.
Dotors stated that the car was one of the first 33's to be imported and that the VIN # (or part of it) may have been changed legally. When asked for documentation, etc, they couldn't provide it.
The Police stated that if the car was pulled over and suspected to have a fake VIN #, they have a right to confiscate the car and hold it till an investigation clears it, which can take over 12 months. At the end the officer stated: "If you have a bad feeling about the VIN #, then walk away and don't buy it"
So that, and the unclear reason why this car had a "tampered" VIN #, was enough to drop the sale.