Years ago, I owned a 70s Chrysler that had some electrical problems. Even though I’d replaced the alternator and voltage regulator, the battery would still die (it was a new battery). I stumbled across a web page dedicated to the cars the other day and it said that this a common problem with early 70s Chryslers. It seems that the alternator would fry the voltage regulator and then overcharge the battery or fail to charge it. Apparently there’s no after-market solution to this problem, so I’m wondering what I could have done to correct the problem. (It was one of the main reasons for getting rid of the car as it had the bad habit of dying for no apparent reason in the middle of nowhere.)
Yes, it was a very common problem. If there were no other faults in the wiring, it was most likely caused by loose/dirty battery connections (usually), or one of the bulkhead or gauge connections between the alternator and the + battery terminal(very rarely). They’re all at the same potential.
Of course, the best solution would be to make sure those connections are right, but you could also carry a spare alternator and regulator in the trunk and watch the amp gauge closely. They’re both cheap and can be changed in under 10 minutes. I did this for years (at that time you could still get diode kits to repair your own alternators, so the expense was minimal).
You could also convert back to the old pre-'69 “open contacts” type regulator. They were a real PItA to get set right, but they were bulletproof.
I don’t understand the concept of “no aftermarket solution” on a Chrysler of that era. There are all sorts of HP alternators and voltage regulator combos you can buy, which are far superior to and more robust than the stock ones. Couple this with some new wiring, check to make sure there are no shorts, and…why wouldn’t it be fixable? 
This topic generally doesn’t come up much on Chrysler discussion lists that I’m a member of. I suspect newer aftermarket voltage regulators have cured this problem.
My Dodge Dart did have an annoying but unrelated “dying in the middle of nowhere” problem due to its electrical system. Faulty contacts in the ammeter could kill all electrical power except the horn. I sanded the corrosion off the contacts and it hasn’t given me any trouble since.
I didn’t mean that it was impossible to fix the problem but AFAIK, there’s no solution to the problem if you want to keep the car 99% stock as there are with some other cars that have problems endemic to them. For example, the original gaskets on the Corvair leaked like a sieve and any replacement gasket you buy for the car now is designed to prevent that from happening. If I were to buy an alternator and voltage regulator for that Chrysler and slap it on the car, it’d still have the problem and no one makes, for example, a resistor that you slip between the voltage regulator and the alternator to prevent overcharging. Its rather odd that no one does make such a solution since some of the most popular models of Chryslers were built during that era and have the same engine combo as mine did.
According to the information on this site, it still seems to be a problem. I don’t know what kind of regulator the guy used when his blew, but from his site it looks like that the ones you’d get at Autozone might still have the problem.