Where is the Location of the Underbelly Subway Station?

The recent spate of articles on the Underbelly project has also spurred great interest in where this mysterious subway station / art gallery is located. The New York Post helped to narrow the location of the gallery citing in a recent article that it is in an abandoned G train station in WIlliamsburg, Brooklyn.

People are flocking the station, trying to get in and have a look. Unfortunately so are the police. The police are also aware of the location and have been sending plains clothes cops there to arrest any tresspassers. Twenty were just rounded up last week.

But where is the station exactly? Here is an excellent guess from the blog Second Avenue Sagas:

Based on the visual evidence, it is in the never-used, once-built shell of a subway station at South 4th St. and Broadway in Brooklyn. I traced the unique origins of this long, lost part of the Second System two years ago, and Subway & Rail has a full gallery of this station online. Built in an age when the city built shell stations for cheap with an eye toward future expansion, this shell has set empty since the day the concrete was poured. Rumor has it that one can access the station via the G train stop at Broadway with the appropriate key.

And Second Avenue Sagas has another post indicating that the Transit Authority is starting to seal it all up.... right around South 4th Street on the G line. Hmmm.

So before it is all sealed up - Are there any brave souls who want to try to access it?