Please help! I'm having a Meltdown!

Ok I have an alternator related question. The car has a new EZ wire harness installed, alternator and battery are all new as well. The car has been out on a few cruises and all seemed to be working fine until I noticed a drop in voltage and she stalled. I noticed on the alternator that on one of the field wire connections that the rubber/plastic washer had melted due to the heat of the headers (I think) and the loose wire was causing the car to stall out. I hooked up the field connector without the rubber insulator washer and now when I turn the key the wires connecting to the ignition are starting to smoke as well as the alternator field wires are hot to touch as well. So my question is about the rubber insulator washer on the alternator. Was it a mistake to try to hook up the wiring on the alternator without it and is this causing the melted wiring?