I know alot of people wonder "will this wheel fit my car" well all wheels are different and the proper offset doesn't necessarily mean the wheel will clear the caliper or the HICAS but based off what I've found on TT.net here are some general guidelines (applies to 17" wheels or bigger). The F1 is the offset based on having the same spaceing as the stock 7.5" wheel (45mm offset). F2 is the offset for the same spaceing as a stock 8.5" wheel up front (35mm offset). R1 is based on the stock 8.5" wheel spacing (35mm offset). R2 is based on the the FAQ that mentions a 9.5" rim can fit with (30mm offset). All offsets are +.
8.5"
F1=32mm
F2=35mm
R1=35mm
R2=43mm

9"
F1=26mm
F2=29mm
R1=29mm
R2=36mm

9.5"
F1=20mm
F2=22mm
R1=22mm
R2=30mm

As for 10" and larger it's hard to say without actually fitting a "dummy" wheel to the car and checking if there will be HICAS contact with 18" and 19" rims.

This is a qoute from Twinturbo.net

And one more for you.
For those who were interested, the wheel offset on the Z32 Naturally
Aspirated is 45mm fornt and rear.

Z32 Twin Turbo is 45mm front, 35mm rear.

Well hope that helps.
I hope these rims arent all "bling" and crap I hate bling on Zs.