I have a 24 Minn Kota trolling motor. I have 2 12 volt deep cycles in series that I use for the trolling motor and a 12 volt deep cycle that I use for starting. I have a Perko 1/2/all/off switch. I want to hook one position of the swicth so to be able to use one of the trolling batteries as a backup. Would I just runs the leads from the numer 2 position to one of the trolling batteries +-, and if so, if I switch to ALL would I have a problem, or is there a simple way to connect all three batteries when not using the trolling motor that they would be charging when the motor's runnning?<br /><br />Thanks for any suggestions.