Brother HL-7050N - Manual (Page 145)

4 - 18 OPTIONS
HL7050_US_UG_FM5.5
3 Loosen the three screws, and then remove the metal plate by
lifting it up slightly.
Figure 4-17
4 Put the four shoulder screws, supplied with the HDD unit, into
the bottom of the HDD.
Figure 4-18