Ricoh M281 Series Service Manual page 331

7. Remove the controller board [A] with the BiCU [B].
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Be careful not to damage the backside of the controller board [A] and the BiCU [B].
8. Remove the controller board [A] from the BiCU [B].
9. Remove the two guide rails [A] from the controller board [B]. (hook×2)
SM 4-137
Electrical Components
D255/D256/M281/M282