The light assembly is held in by a few screws, they aren't an issue. Sealing and REALLY holding the tail light in is silicon, you need to scrape it out.
Once thats all done, gently knock the central supporting bolt with a mallet to loosen it up. It should be out after that.
I tried, it's hard and a real b**ch.
I'll try and find the link.
EDIT: sorry just read the end of the first post. I don't know how to get the indicator out.