The Green Card is the document given at the time of transfer of title and registration to someone who bought a car used, drove it in a state other than NJ, and now is transferring it to NJ in good standing. Effective 2010, inspection of such cars can be deferred for 5 years. The owner is supposed to present the Green Card to an inspection center and receive a decal. I filed mine in a drawer and now can't locate it.
I'm not sure what you mean by green card for inspection decal. Given that I would suggest going to a motor vehicle office to discuss the steps required. However if you have a license and registration/ insurance card for the vehicle you should be able to go to an inspection station and have your car inspected.
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