You should treat us to some good photos, including the BB cable thing. As you may already know, this was built by Miyata for Ben Lawee the West Coast importer and sounds like one of their best. You can try some of the Blackburn fender mount doohickies for the rear DOs, but maybe you'll have to settle for a shorty front fender. I haven't yet done a 650B conversion, but here's a link to some info:
http://www.freewebs.com/650b/