Quote:

The closer to the battery, the better because the battery helps filter electrical noise.



Horrible misinformation. The electrical noise would be no different anywhere on the charging circuit. The only thing that would differ would be the voltage itself as there will be small drops across various connections (i.e. bulkhead). The "shakiness" of the voltage will be no different as it's all the same circuit.

The only thing you gain from wiring on the battery (or starter relay) is pulling additional current through the dash harness (unless you have done a bypass), making the car that much more unsafe not mention making the ammeter totally unreliable.

The "noise" from radio is not necessarily from the alternator but from the ignition circuit, not the alternator. This is EMF and if present on one side of the charging circuit, will also be present at the other. If you have noise now, wiring from the battery probably won't help.

I pull my two electric fan relay loads from the alternator stud. No noise on my radio and my ammeter is dead accurate.