A little OT but I saw someone mention two fuses on the ALT wire:
You would not need a second fuse on the Main ALT BATT + wire. A fuse near the battery is all you would need. The reason you fuse a wire is in case of an accident, any wire going from the battery should be fused and within close proximity to the battery. The reason for this is a wire that is 18' long going through your car has a very high risk of shorting in an accident. 0 gauge at a dead short with 1200CCA battery will make some nice sparks. The Fuse blows in case of a short and stop power within 1-2' of the battery.
Now in regards to your alternator. Once the engine stops, the ALT is not making power so it no longer is a source that is creating power. A battery, with the car off, still holds voltage. An alternator that is not spinning creates nothing and is storing nothing therefore the + BATT ALT wire needs no fuse close to the alternator. You could argue a point that the wire does get pinched and the motor is still turning, but I really think that would be very slim. I mean for the wire to be pinched and not effect the pulley system or alingment of the belt that drives the ALT would most likely be the result of poor wire routing more so then anything else.