Regarding all the CSC talk, here is something to consider. Make of it what you will. This quote is from Ryan, the producer of the RJM adjustable clutch pedal. It's part of post #258 from the following thread:
RJM Clutch Pedal System for 370Z - Fully Customizable Clutch Feel & Stroke
"The RJM pedal safely and effectively reduces master cylinder stroke volume and lowers the engagement point taking away that excess CSC stroke that leads to failures. This reduction of MC & CSC stroke when installing an RJM pedal is why the stress on the factory CSC is greatly reduced to where the CSC is no longer in danger of maxing out and popping the seals with every stroke and there's less overall seal wear for a longer overall service life."
If anyone is that concerned with the eventual failure of the CSC, a preventive step is to install the RJM clutch pedal and enjoy the side (or main, depending upon how you see it) benefit of having smooth and consistent gear changes and clutch engagement, which a stock 370Z certainly doesn't have.