one thing i noticed when looking for my r33 for about 8 months was that most skylines' had digits on the odometers that were out of alignment...this to me was a sure sign that someone tampered with the clock readings...out of dozens of r33's i looked at only 3 had 'aligned digits' on the clock as well as almost no wear on interior parts like pedals, handbrake, gear stick, seats, carpet etc. etc.
interestingly these 3 were all privately imported by people who went to japan to buy their skylines...
i am the proud owner of one of the 3, test done on the car prior to purchase also claimed km's were genuine, the engine is very quiet at idle i.e no bearing noises, gearbox is very good also.
the car had 50+ kms; after two years and as driven daily now has 90+ and never missed a beat.
car also came with a lot of paperwork such as auction documents, cancellation of rego in Japan etc., and seem to support the odometer reading.
but there is always a small doubt in my mind.......