Need advice on buying an out of state GN..to California

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So I'm looking at an out of state 87 GN..and was wonderful what steps I need to take to get it all smogged and registered in California....the owner claims the car is originally from California and is 100% stock...has anyone out there bought a out of state GN that could give me some advice on what loops you would have to jump through with California DMV? Thank you in advance

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