very interesting stuff.
was the car built by nissan works team or a nissan based team?
there are few incarnations around based on the vq, I remember someone trying to sell what he called a vq38 somewhere recently. similar to your case, he didnt have a details of the built except that its been stroked to 3.8 and was raced in the states.
I would be surprised if the internal are stock. I seem to remember that the con rods on the vq35de were not the strongest nissan has produced so they were a definite upgrade for compitition engine