Ok technically they are a series 1.5 1995 model. The series 1.5 had a series II rear (colour coded SKYLINE garnish and spoiler update) with a slightly updated front bumper and grill. Drivers airbag was standard on them and the passenger airbag was optional.
However i still class it as a series 1 since it has series 1 headlights (or in the case of the photo i posted it has series III GTR headlights, which as we all know are the same shape as series 1 headlights) and had a series 1 engine. Series II were 1996-1997 and had a normal series II empty grill, not the one above.