If it's the Archives facility on the lot, then it is likely the offices in the Frank Wells building. The ground floor Archive/Library has a nice area for displays - cases, bookshelves and the like. I get the impression that some stuff is permanent and some stuff rotates. This area is open to anyone who happens to be on the lot.
Upstairs is another office. Not quite as formal or accessible. More of a storage area with these cool rolling shelves that allow you to cram a lot of stuff into a small area (like we all need). Vincent and a Humanoid seemed to be on long-term display there, as was some maquettes from Narnia and a Rocketeer backpack.
The Palomino was there one time that I was on the lot for unrelated business and stopped by. The next time - it was gone. I get the impression that there is an off-site storage facility where all the bigger stuff, or the items in long-term storage, are kept. I somehow imagine that place to be like the warehouse at the end of "Raiders of the Lost Ark", 'cept with ears........
I have a feeling that it's a crap shoot - you'll see what they have out. Either way, I really like going to that lot in general and the Archives in particular. Have fun.