Turn your lights on full beam to create a load on the alternator. I asked a few times what model fluke you are using or is the multimeter a cheap non brand. With respect you appear to have little electrical experence and would suggest that you read up on electrical fundamentals that will greatly help you understand your troubleshooting. High ripple may well mean a problem with the alternator diodes.So when you do this ripple test, do you turn all the accessories on? Like radio, lights, hvac etc?