i replaced the alternator and now the battery light comes on and stays on.

yes.. both with the car running.. and yes i held the trip button to and scrolled through till i got voltage while running.. and 12.6 with car off..

well,all checks are good.try disconnecting the battery again for a few minutes,the reconnect?everything good and tight,and all is hooked back up,grounds clean and tight.usually when battery light comes on,it indicates that the alternator is not charging.

i tried disconnecting the battery again and the light came right back on.. i will take back the alternator and try this again..

that was gonna be my next suggestion.post findings.have seen many times,bad, new, right out of the box,regulators bad!