Can't remove tail light. Am I overlooking a fixing?

[Tommygunn]

I'm trying to remove the tail light units from my 2002 Toyota Yaris.
I've removed the central nut from the inside but the light unit won't budge. There are two other protuberances coming through the metal body work which are a plastic spigot, lower left of the metal bolt, and rubber type insert further away to the upper right.

I'm also presuming that there is some stiction with the gasket.

Even with the nut removed the outside of the unit has zero movement while the inside has a slight amount of flex.

Am I missing something?

Here's a shot from the inside of my Yaris.


Here is a shot of what the light unit looks like that I pulled from the web.



Tom.