---

In most of the rewiring I have done, you have a terminal block for the positive and a separate one for the negative. Yes you can wire the cigarette lighter to the fuse block and tie the negative to the rest of the others. As for the size fuse, I am not familiar with that Blue Sea model, but if it has one fuse for the whole block, you will want to add up the amps that all the electronics on it can handle and size the fuse accordingly. If it has separate fuses for each of the connections, then the fuse would be the one recommended for that piece of electronic equipment. Cigarette lighters you should look at what you are plugging into them to size the fuse. Hope this helps.

Good luck!:D