Apple Xserve (Early 2008) - Manual (Page 14)

14 Chapter 1 Installing the Xserve
Step 3: Mount Rails Loosely in the Rack
1 Place an assembled rail in the rack (it will support itself temporarily while you gather
the fasteners). The way you fit the rail depends on the rack.
 If you have a threaded-hole rack, start with the rail flanges outside the rack posts and
compress the rail into position.
Position the spacer
over the threaded guide
on the rail assembly.
This end is up.
Compress the rails
so that they fit on the
outside of the rack posts.
Use either eight 10-32 or eight
M5 screws (supplied), depending on
which type your rack requires.