I have seen a few where the coil, gene and battery etc have been cooked when the relay points stick in the regulator.. they can drop a battery in seconds.. They look just like a set of large contact points and it doesn't hurt to clean them every now and then so they don't stick.. We actually put a match stick in between the points once to drive home after the regulator decided to play silly buggers..
Not recommended but it can get you home at least.. Likewise some older stuff is pretty darn iffy ..
How many don't like the idea of an alternator.??? Seems the way to go if you don't mind the modern bits..