I've purchased all the supplies to build some closet organization units for my master closet. The closet is a small walk in: 75x84 inches. My plan includes corner shelves with long hanging space on the back wall and double hanging space on the side walls. I designed the system on a website but didn't purchase the system because I thought I could make it myself for much less. I am at a loss as to how to attach the units to the wall when I am done! I don't want them to sit on the floor because I have base boards that wont allow the units to lie flush with the walls. Any suggestions for how to attach shelving units to the walls?