The suspension system on the Z is pretty good, but it can certainly be improved upon.  At around 70,000 miles, it was time to do some replacements.  And I took the opportunity to lower the ride 0.8".  Unfortunately, this also requires several other adjustments - adjustable tension rods, a camber correction kit.  I also needed to replace the shocks, but opted for stock replacements instead of the popular KYBs.  I did this to keep the in-cockpit adjustability feature that is standard on the Z.

Above - Stock shocks in Nissan packaging

Above - Box the lowering springs came in; Below - The springs inside the box

Above - A view of a disassembles stock upper shock mount.  Notice the rather lame seal in red/orange.  On the right side are rubber "boots" that fit around the top and bottom of the springs.  They were reused; no discernable wear.

Above - The adjustable tension rods from SGP.  They shouldn't rust.  I also got the  300 degree camber correction kit installed, but no pictures.  This is a great alternative instead of buying the Stillen adjustable A-Arms.  I was back within stock specs after installation.

Go to page 2 for more pics (link on the upper-left).