Use external voltage regulator with HO alternator?

I just replaced the stock alternator in my Honda Accord with a HO (120 amps at 2,000 RPM) rebuilt alternator. I replaced the alternator because I was getting a general dimming in my lights when cranking the system. I am still getting the same dimming with my new alternator, apparently because the internal voltage regulator in the new alternator is improper for my usage....It was suggested to me that I have an external voltage regulator somehow retrofitted to my new alternator (and disable the internal voltage regulator) in order to better regulate how much power is sent to the battery. Does this sound like a feasible solution to my dimming problem? Has anyone else used an external voltage regulator?

First off are you using any capacitors? On a 120 amp alternator you do not need an external regulator. It’s cheaper to take back your alternator and have it fixed. First off there is no way to disable the internal regulator with out opening up the alternator anyway. Also have you upgraded the cable between the alternator and the battery, along with the ground wires. If not you may want to consider doing that since you now have a higher output alternator.