New ChevyDuty harness, new 12v alt with external regulator, new battery with 1 ga. cables and new ground strap (I even exchanged the alt & reg.)and a new headlight and dimmer switch, also new coil with resistor. But...tail light fuse blows with truck running after time, sometimes lights die or dim at intersections, horn blows for no reason, battery won't start truck even though it reads 12v, alt won't charge battery and now it won't even jump start. What is going on here???????
