Nice lookin' rig feesh! Looks pretty stable according to that pic above.

You should just be able to remove the switch from the head and extend the wiring and re-mount the switch in a plastic rain-tight electrical box, then go to Radio Shack and get a knob for it.

Been a while since I'd posted them threads on the stick-steering, but I think I'd posted most of my "thoughts" and pics there. I haven't actually done it, but if I can answer any questions, don't hesitate to ask.