Routing the wires is no problem! No worries there. I have never thought of this before, but if you find some mirrors with signal in them you like, and they attatch in a ball joint, just use that joint and change it to a set of ball joint bar end mirrors! Use the mounts from bar ends with ball joints, to the mirrors that are post mount with ball joints, simply use the combonation of mounts and mirrors you desire! Ball joint mirrors are typically universal in joint size!