Only difference is that bolt/stud at the top.I installed one on a Z32 car that I had a while back..That stud is there to attach the skidplate/wind deflector under the cars nose because the popcharger replaces the whole airbox which sits between the headlights,sort of in the bumper.
Interesting note,if you dont attach the skidplate,it will cause a weird problem at highway speed.There is some weird turbulence or something aerodynamically that makes the car want to fall on its face or stall at those speeds.
I remember reading alot of people having this happen to their Zs .
Anyway back on topic.
What ever happenned to this?