I'm starting to think its an epidemic..

definately need to have a ground for alternator and voltage regulator and always a good idea to unhook the battery when changing out the components,I have a test light that you hook up to the battery and you can check for ground and for hot red light for hot green for ground but they also sell one called a power probe that is slick as can be even has a buzzer and a button to feed power to something lil' on the pricey side but very valuable tool for diagnosing problems