The front of the V-berth is a good location for the battery selector, but why 
do you need that much power? My battery gives me 185 amp hours. Running 
everything I have, I have approximately 18 hours of power. That includes all 
the lights, pumps (washdown pump also...big draw) and stereo.
The second battery just adds a lot of weight unless you are doing some 
serious long distance sailing and won't have shore power capabilities for 
more than a week.

Rummy......a true believer in the K.I.S.S. system.