You dont want to figure out what fuse to use by adding your amps fuses. You want to go by the rating of the size of wire you use. If you use too large of a fuse, your power line can burn up (taking your car with it) before it blows the fuse. Since you're using a 4awg wire, I'd stay between a 125A and 150A fuse. Seeing that amp is only gonna pull around 65A, you'd be fine with an 80A fuse. But most kits will come with a fuse and fuse holder. I would look for a kit the uses ANL type fuses. The AGU fuses (look like glass tubes) typically have crappy holders that get corroded and add resistance to your line. As for a kit, thats up to you. I spend the good money for good wires because its the backbone of your system.