Originally Posted by
greenman100
I have never seen an accessory wired to the alternator post. That's the only connection point that's 'behind' the 75/100A fuse. Wired anywhere else, the accessory pulls through that fuse.
Longfellow: Change the fuse if and only if you've upgraded the "big three" - alt to batt, batt to gnd, eng block to gnd. Otherwise, you're setting yourself up for a fire.
Generally i've usually got a 8, or 4GA wire from alternator post to battery anyway.
Stereo, direct 4, or dual 4 to battery going through fuse or circuit breaker.
Of course other than my nissan, everything i've had for the past 10 yrs or so has been 100+A, and usually 140A, current one in my build is 155A...