[KevinP73]

I have in my shop a '65 356 C Coupe. The car is in remarkable condition considering it's age. The hard part is that it has 9,615 miles on the odometer. The current owner has known of this car since the late 70's and says the car has not been driven since they became aware of it. The last registration tag for the car was 1977 and this tag was never even put on the car. It's still stapled to the registration card in the original DMV envelope.
As the story goes the original owner didn't like the car for reasons unkown to us and very seldom drove it. He had an Alfa Romeo that he drove instead. At some point in time around the end of '76 the car was painted, changed from it's original Red to the Green like his Alfa. He wasn't happy with either not happy with the job in general or the way it looked on the car. After picking up the car from the paint shop (or shortly then after) he was rear ended lightly. The story goes that he was so unhappy that he just parked it. The car is indeed green over an original red and it still has the minor rear damage that supports the story so far. Also the registration tag in the original envelope supports the story so far.
My question is how could I go about discounting or proving that the milage is accurate? The original tires rotted off long ago although the spare is still with a box of parts that came with it.
The current owner tried to get the car running so the coil has been replaced with a new part but the rest of the motor parts should be original. I need to buy a good reference guide but don't know which would be the best.
Any other suggestions would be greatly appreciated.