If you look at production date ( plate or label on the door or B pillar ) , most of the time it doesn't match with sticker or plate in the engine compartment . Like I stated before , when you are dealing with mid year production , it can go either way . The engine compartment label will be the correct year to go by and the VIN will match it .
Part number would be an ideal way to order part . They are few parts on the car don't have part number and/or missing or damaged . When you call in for a part , you need to give correct year model ( label in the engine compartment ) . Most dealers prefer VIN and sometimes will ask for production date , especially for model like the 260Z .
Like 2014 cars , some will be built in 2013 , that don't make them 2013 models . I always use engine compartment label and VIN ( should the 10th digit on late models ) . The above picture is an S130 ( 280ZX ) , to my knowledge , 79-83 are S130s .