Epson Equity 320SX PLUS - Manual (Page 144)

6. Notice that there are two tabs facing downward on one
edge of the mounting plate. These tabs will fit into two
slots in the right side of the subassembly.
Guide the tabs into the slots and tilt the top of the drive
toward the subassembly. Then align the retaining screw
hole on the mounting plate with the hole in the
subassembly bracket.
bracket
7-16
Installing and Removing Disk Drives