6. Remove the four screws (P2.6 x 4), three screws (B3 x 6), and six hexagon screws to remove the MIX-54 board.
Flexible flat cable (50 core)
MIX-54 board
CN4900
P2.6 x 4 
P2.6 x 4 
B3 x 6 
Hexagon screw
Hexagon screw
7. Install the removed parts by reversing the steps of removal.
1-3-9.  KY-671 Board
Preparation
1. Remove the top panel assembly. (Refer to “1-3-1. Top Panel Assembly”.)
Procedure
1. Remove the seven audio fader knobs and the volume knob.
2. Disconnect the flexible board from the connector CN405 on the KY-671 board.
3. Disconnect the flexible board from the connector CN407 on the KY-671 board.
MCS-8M
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