When I last had to lower my Z's clutch I was working on a 2003 350Z. That was 2 Z's ago, but the 370Z I bought today is going to need the same treatment. The salesman I asked about the clutch today said that they used to be adjustable, but nowadays the Z's have hydraulic clutches, which can no longer be lowered.
We shall see! But I was digging around in my browser bookmarks and found this thread: it was the one in an Infiniti forum but it walked me through the clutch job 7 years ago and I reckon I'm going to go back and study it and the photos all over again.
It's a keeper:
http://www.freshalloy.com/forums/showthread.php?t=73620