Re: additional fuel tank
You need to be concerned about the side-to-side balance of the boat, if you install a fuel tank that is not centered in the hull. You will also want a mechanical brass/bronze "selector" valve to select the new tank or the old tank. A "Y" fitting will not work. You also need to install the thru hull fill and vent fittings, and ground the tank. What about a gauge? You can wire your current dash-mounted gauge thru a selector switch(SPDT Switch), so you can choose which tank you are monitoring.
Hope it helps....
