To locate the eighth rack hole, count eight holes upward from the bottom rail location peg.
Figure 1: Cage nut installed in a square-hole rack
 
 | 1 Rail-location pegs | 2 Cage nut | 
Figure 2: Rail-location pegs from inside of the rail flange and the clip nut
 
 | 1 Rail location pegs from inside of the rail flange | 2 Clip nut | 
Make sure the rail flange aligns with the inside of the rack flange and the rail label faces the inside of the rack.
Figure 3: Rail-location pegs and a square-hole rack
 
 | 1 Rail-location pegs | 2 Cage nut | 
Figure 4: Rail extended to holes in the back of the rack
 
 Figure 5: The locking screws and side of the rail
