whop, I can't believe nobody's answered this ...we got some ''jamb-up'' electrical guys...
the light and bilge-pump need to go to a switch on the dash...actually the bilge goes to two switches; dash AND auto-float switch that should be in your bilge...if not one , ADD it...
If no instructions w/ yours, e-mail these guys for same on the battery switch...
http://www.cgedwards.com/Perko/pko13.html
Good luck w /your V-20 and let us know how these things work out ;) ...