Battery in the trunk, huh? Consider this-you have a 2.5" rubber hose that runs through your trunk that is connected to your gas tank. These hose are nortorious for developing cracks and leaking gas into the trunk. Late cars also have a vapor seperator inside the trunk. It is also connected to the gas tank with a rubber hose. So picture this, you car has been sitting out in the sun all day. Gas vapors have filled up your more or less sealed trunk through a dryrotted hose on your fill line. You have a loose conection on your battery, so you get a spark in an explosive atomsphere. What happens? It won't be pretty. Think a boat battery box is going to keep the gas fumes out? May never happen. Then again, it only has to happen once to destroy a perfectly good MGB and it pasengers. Here in Louisana, even boats that have a gas tank in a enclosed area are required to have ventilation to prevent an explosive mixture from igniting. If all of this is not enough, consider that batteries give off both hydrogen gas and sulfuric acid vapors when they are charged. Acid fumes will eventually ruin everything in the trunk. This stuff may never happen to you, but is it worth the risk?