can you guys help me? i'm trying to install a duel battery system into my defender 90 2.8i. i'm supposed to connect the isolator unit to the terminal marked (b+) on the alternator,but there is already a live wire there that is giving a constant positive reading even when the vehicle is off!! there is anouther connection point just under the (b+) terminal that only gives a reading when the ignition key is turned. could i connect the isolator to this connection or not? :drive: