Ricoh D146 Service Manual page 340

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3. Replace the contactless guide plate (front) [A] with the contact guide plate (front) [B]. ( ×1)
There is a hole in the contact guide plate (front).
4. Replace the contactless guide plate (rear) [A] with the contact guide plate (rear) [B].
There is a hole in the contact guide plate (rear).
D146/D147/D148/D149/D150 4-46 SM