Rear Defroster - Vertical/Horizontal

[NCLarry]

I've just acquired (this past Saturday) a 1971 240Z. I'm finding some parts seem to have been replaced with pieces from later model years (e.g., the hood).

I suspect the rear hatch gate is not original as well as the defroster elements run horizontally... I thought on the 240s the ran vertical. Which way did they run in 1971 and for a bonus, when did they change?

[Bambikiller240]

The 71 I used to own, had Vertical lines, the early 72 I currently own has Vertical lines, the 73 I previously owned had Horizontal lines