I'm thinking about picking up another battery. I hear its pretty simple to instal. You need an isolator and a battery box. I think Im going to build the battery box and carpet it, but I have power wire running from the + on my battery up front to the rear of my amp. Could I just splice an isolator say about 12" away from my new battery and then connect the wire that was coming from up front to the + terminal on the battery in the back, and then take a wire from the negative part of the battery and ground it to the chassi, the same as I did for my ground? Would this help my lights from dimming as much as they do now? Would it help it, so I wouldn't have to jump my car if one battery died?
You have the right logic. With an isolator installed, you won't have any problem starting the car cause the batteries won't see each other. For installation, connect the isolator close to the first battery. On the isolator, you'll see battery1 and battery2, pos from alternator, and ignition. It's quite simple as you can see, just connect each wire to the proper label. The ground gets connected to the chassis. You can use the existing wire that goes to the back on the 2nd battery. Then connect the amp to the battery.