hi again grady -

another thought is to travel a little bit to new hampshire - check out nashua, merrimack, manch-vegas ( manchester ) .. the mills / factories there are huge like some of the ones in lowel and lawrence... not small ones like in slatersville ...

you might be able to find a "industrial" tourbook - i think the sia put one out a few years ago or if you contact the state historic preservation office in whatever state you want to photograph in, they might be able to tell you if a book or "inventory" has been done ...

good luck!

- john