[FL911SC]

Perhaps another silly question, but that has never stopped me before.
This past weekend, during my first autocross, I found out the hard way that my battery is not being properly changed. I had no problem starting the car until it was on the grid and my turn to go. I turned the key and got nothing. I was able to push start the car and just left it running between runs.

So this week I have been reading up on alternators, voltage regulators, generator lights, blue wires and the other places I will need to troubleshoot when I get home.
During my reading, I have found that when replacing the alternator, it is preferred to replace it with one which has an internal voltage regulator.

My question is, why is the internal voltage regulator preferred over the external one I have now? Even the tech. article the covers the change does not say why you should do this. Additionally it is not one of the “Recommended Upgrades” listed on this site. Intuition would say that the external setup would be preferred since it can be easily accessed for testing and/or replacement. But intuition probably isn’t right on this one and I just want to understand why.

And just to get this question out of the why now, will the new style (internal VR) alternator mount to and fit into the current fan shroud without modification to the shroud? I read the air duct might have to be modified, but is there anything else such as the shroud?

Thanks,
Keith
’79 911SC Targa with original alternator.