Is the switch in the latch assembly or is there some mercury switch in the light case?
Anyone know offhand?

 

Good question! Didn't see anything on the parts catalog...

 

I wondered about that too. But I think that the light is activated by the engine (and trunk) lid release itself. In my garage with no lights on, I noticed that when I hit the front trunk release I could see that the engine bay light came on as well even though it was closed and latched.

So I figure there is a relay somewhere that is tied to the front and rear lids.