Anyone ever wonder if, Because standard Toyota alternators are about 80 - 90 amps, So technically there shouldn't be much more than say 100 amps draw, that would mean the alternator is on its knees and power is coming from the battery to help supply an unusually heavy demand.
So if you used a 200 amp fuse, well the battery alone wouldn't really have that sort of power on it's own would it? so technically it would never serve it's purpose, now if you used a 100 amp fuse would you not risk it blowing out while driving causing a potential danger if for example overtaking?
Would it perhaps be best to run no fuse, but to take an extra percaution like using corrugated plastic wrap around your positive wire?