The Capcom Special Selection Rockman Xover art book is now available in Japan. The pages within shed light on many unused OVER-1 designs, including some truly off-the-wall concepts. For example, OVER-C. It's a Cinnamon-cat-thing.
These images were graciously provided by Capcom Unity member MegaModo. I've tossed up a few after the jump. For the rest, scope out this thread here.