Electrical help needed

[2500HD]

I replaced all of the A/C ducts on Sunday and had the doors open for most of the day. When i finished the truck was slow to start but finally kicked off and ran and idled great. the rest of the day it was slower than normal but started each time. it started this morning and i made a stop before work and it would not start. jumped it off and it would not start later in the day. i drove to my over priced local battery guy and with the truck off and a load on the battery i had less than 10 volts so a new battery was put in and it started and idled higher than normal and very rough. While running it showed 12.4 volts so i bought and installed a voltage requlator. still idled high and rough. set the timing to 8 degrees without much change. While changing the regulator i found a green wire that was capped off coming out of the harness that supplies the regulator. I do not have a volt meter at home so will have to check the current volts latter.

Before changing the battery it idled between 650 and 700 and smooth as butter. It now idles at 850 or 900 and like a plug wire if off.

Anyone have any ideas?