That's a tough challenge indeed. As great an idea as this project is, I believe that the biggest challenge will be, not only to sort out the categories, but to figure out who and which ones go where.
My Grandfather was one of the Construction Workers when the WTC was being built. He hauled material to and from the site. I remember him telling me a little about the construction.
I've also got 2 NYPD Cousin's who were fortunate enough to survive the second tower coming down. They were trying to evacuate the second tower and, when they realized it was falling, they ran out while helping who they could on the way.
I was born in NYC and still have allot of family still there.
This was a horrible event... :-((