The VN Group A was a special run of Commodores to homologate the car for racing. They’re now collectable and worth $37,000-$45,000 depending on condition, kilometres etc.

HSV produced 500 SS Group A versions of the Commodore in 1991 to homologate it for racing, i.e., Bathurst. It sounds like one of those, maybe built after the introduction of the VP in September 1991.

Confirming genuine classics can be difficult and requires intimate knowledge of the make and model to be certain.

I would contact Holden's customer assistance people, give them the id numbers of your car and ask them to check against their production records.

If they can't do that contact a club such as an HSV Owners Club and ask them to help you. There isn't a club in the NT, so contact another state's club.

A guiding range for the value of your car is $38,000 to $46,000, but it can vary widely depending on originality, condition, kilometres done etc.