Three seperate unrelated points here:
1) Nice car looks neat.
2) It's fraud when you represent a car as something it is not and have paper made up to substantiate your fraudulent misrepresentation. If there's evidence to establish the seller created the car or doctored the docs to make it an LS6 and then represented it as one when he sold it, he's in a world of trouble liability-wise in a civil suit for money damages.
3) Since the value is well above the minimum standard for wire fraud or mail fraud, if the car is fake he is also criminally prosecutable for a 5 or 10 year Federal prison sentence since he most likely used a telephone, the internet or the mail for some part of the transaction.
class dismissed.