quawk said:
Would you agree with Tornado that using LEDs may hasten the demise of the original Zener regulator because of it needing to pass additional current to ground because of the LEDs using less power/current/watts than the original incandescents?
I would say no. For the following simple reason. If you don't have a headlight on, which normally means no tail light on, and you are not using your turn indicators, you have no lighting load on the system. And the zener can handle that situation without a problem because it was designed to do so.
In which case, it doesn't matter if you are running LED or incandescent bulbs because the system doesn't see that load.
If you add a high output alternator, that could change the situation, but then you probably dumped the zener. And changed the question.