Brother MP-21C Service Manual page 63

(2) Remove the two screws securing the Ink head base unit. Remove the Ink head
base unit from the Chassis center ASSY by lifting the left hand end of the Ink head
base unit then moving it to the left to release the hooks at the right hand end.
Screw, bind M26x4
Boss
<Reassembly>
Note: When replacing the Ink head base unit, be sure to remove the four
protective parts fitted on the Ink needles, which are positioned behind the
shutters.
(3) Supporting the Ink head base unit, move the Carriage ASSY to the position
indicated in the illustration below. Remove the two screws, then remove the Print
head and the Ink head base unit together from the Carriage ASSY.
Screw, bind M2x8
Print head
Carriage guide
Ink head base unit
Fig. 3.11
Carriage ASSY
Carriage ASSY
Fig. 3.12
III-10
Shutter
Hook
Chassis center ASSY