[NurseBen]

What's a "bus type inline heater"? It has a wire coming off the bottom and heads up to the grill with a plug on it. The truck came from CO and was used to plow snow at an egg plant and I am having issues with the electrical. It has a switch on the dash that if turned on the headlights go out, so I assume it was for some kind of plow lights. I installed a new alt, coil, wires, distributer and was running great. All of a sudden (weeks after work was done) it won't hold a charge, I'll turn the headlights on and the gauge on the dash drops a quarter down, then if I turn the heater on it will drop all the way down. Do I have a bad ground with the headlights? If I am just driving with nothing on it the gauge stays right in the middle. Thank you everyone for your help.