you dont need to run a fuse, theres no way ur cable can get damaged if u reloacted it properly. When i did mine in my 32 gtr, i ran 0 gauge from the front, under the inner guard, through the firewall, under the carpet, under the rear seat, and into the boot to the battery. Also i've got a 2 gauge ground on the battery.
You will have to use larger gauge wire to get the correct ampage to ur alternater