Ricoh D009 Service Manual page 193

7. Keep the right door fully open.
8. Push up the duplex unit a little bit, while pressing the bracket [D] to lock the spring [E].
Do not let the duplex unit open fully before releasing the wire (step 9).
Otherwise, the lock for the spring [E] is released.
9. Wire [F] ( x 1)
SM 3-63
Duplex
D009/D011/D012/D013