No such animal
The G/N is essentially a very exclusive color/dress package of the turbo Regal; Black lacquer; black-out trim, G/N callouts & special interior colors, all a package deal. It's what makes a G/N a G/N.
Here is a link that will help:
Turbo Regal Vehicle Identification Numbers
in a nut shell:
VINs and RPO Service Labels
Ken Mosher
Vehicle Identification Numbers (VINs)
The following diagram shows the location of the VIN plate on the G Bodys.
There is no way to determine if the car is truly a GN via the VIN (vs. a Turbo Regal as determined by VIN digit 8 = 7 for 1986/87 or VIN digit 8 = 9 for 1984/85 TRs). A better way is to look at the RPO sticker in the trunk as described below. This sticker should have a matching VIN with the VIN plate.
General VIN decoding for 1987 Buicks
Example: 1G4GJ117XHP400001 for a 1987 Grand National:
1 = Manufacturing Country (USA)
G = Manufacturer (GM)
4 = Division (1=Chevy, 2=Pontiac, 3=Oldsmobile, 4=Buick, 5=GMC, 6=Cadillac)
G = Series (G body)
J = Sales/Option level (Regal ... K was supposed to be GN, but wasn't used)
1 = Body Code (2 Door Coupe)
1 = Restraint System (manual belts)
7 = Engine Code (LC2 3.8L SFI Turbo)
X - Check Digit
H = Model year (H = 1987)
P = Plant Code (Pontiac Michigan)
400001 = Serial number
Thanks to: Ken Mosher & GN T-Type.org
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