Welcome Garry, and congrats on your new Trillium
if anyone can help, can you email me at...
I kind of hope people will chime in here, instead of via e-mail, because I always like to learn new things; once I see a question like this, I'm curious how it will all turn out
I think that with many of these stoves, the top metal part comes off to reveal the attachments beneath (the lower tray beneath the burner elements has a lip that you will then see, which is probably riveted or screwed to the counter), although I don't speak from direct experience.
House sinks have clips under the rim to hold them on; if the Trillium
sink has those you can probably access them after you have a hole where the stove was.
One comment on the scheme: On boats, the sink is always a coveted spot to put things so that they'll stay put, and a drain can be nice when brushing teeth or pouring out coffee. If it were me I might remove the faucet (to make it so you can have a flush counter if you want it) but not the sink. Then you can make a cover, yet still have it there for storage or occasional use (or still remove it later).