When I was in the closet remodeling industry, I did see one such dry cleaner's system in a residence. It went up into the finished attic and made a series of turns before coming back down. I've never seen one woman that had so many clothes. It was rather disgusting, frankly. In your case of 2' x 2', you might use the over/under or upper/lower concept devoting 42" to each section. If you have an 8' ceiling, you can get two partitions and hang them from a rail on the back wall as high as possible, using a fixed shelf at the top to hold the partitions together and set your two rails to whatever height you need. Check out the California Closets offerings.