Gregory's Server
We're in!
The retention mechanism (handle & clip) will almost certainly fall on the table, so make sure you rescue them.
There may also be a plastic shim to keep the ROSA / TOSA securely in place, but not all modules have this.
Finally, a single screw will usually allow the PCB to lift away from the chassis. There are sometimes metal features on the chassis to "hold" the PCB at the far end from the screw, but not always - just be gentle and it'll come out.
Watch out for a thermal interface!
Finally, here are all the bits.
No thermal interface in this module, which was a little unexpected. If I remember correctly, the GPON modules I've opened had it... 80km is definately further, but perhaps 100Mbit/s is the key factor here for power dissipation.