Well first off , If wired straight to the battery, make sure you use an in line fuse holder, as waterproof as you can find. I can't remember what amp mine is, but it should say in the manual of any downrigger you buy. I also have scotty's and would echo SeaDNA that they are what most people use and there is a reason for that. Low draw from your battery, good warranty, and pretty easy to maintain. I also agree to put the scotty socket somewhere out of the rain and spray, since they do corrode and this will cause problems,also use some dielectric silicone inside the socket and on the other fitting, that fits inside the socket. I mounted mine on the under side of the starboard backing plate that I used. You can't even see them since they are tucked away so nicely. And as far as the 2nd battery It is a good idea to have two, or get the charging system for your kicker if one is available. I'm planning on doing both. But I have a wallas and a wife that likes to keep it running all the time. But on a sixteen I would probably just go with the charger for the kicker. Have fun!!