lol, well done Ferryman, it was DE HOORN indeed - I was convinced that you wouldn't find the answer on Google (I've checked it myself!
)
Here's SOUND OF SLEAT in her original role as the River Maas ferry
She has hardly been altered, apart from modifications to the end ramps.
In 2004 she was sold by Western Ferries, and is now a diving training vessel based at Holy Loch near Dunoon - only a stone's throw from her former Western Ferries route.