With wiring harnesses, if you're gonna' go through the whole bike, you can use split loom:
http://www.cabletiesandmore.com/wire...FWICQAodl0lm9Q
We install driver assist systems in snowplows in Alaska, and they are really hard on wiring (vibration, corrosive de-icers, etc.) we loom EVERYTHING and haven't had any wiring failures. The stuff is cheap, and works great.