To facilitate transport, the bridge will be removable.
To hold it in place while remaining removable, I made a sort of plug : I used wood stocks, glued on each side, and 4mm aluminum rods.

The aluminium rods are glued on the neck side. Everything is held in place during bonding.

If a metal plate is screwed onto the bridge wood part to prevent the rods to go too far and damaging the optical fiber and LED to come.

It finally slid a little too well, so I put some masking tape on the rods to slightly enlarge the diameter.