Mark,
I forgot to look at the one on Torsk to see how it is mounted while I was up there last weekend, sorry.
What you need to look for is the piping for the ships horn and then you will see a bracket where the ships horn handle goes, you will probably have to get a nut and bolt for it to work, the piping should have a valve on top with IF I remember correctly it is a poppet valve actuator (valve body should have a nipple for the actuator to press on to actuate it) and the handle was stowed in the close proximity if not still on the valve just in the locked up position or locked to keep it from being in advertantly actuated