1981 Eldorado not charging and burning out alternators.

Hey guys I have an 81 eldorado with the 8-6-4 motor and have been having a serious issue with the charging system. I put a brand new battery and have went through 3 alternators. The first alternator was from pep boys. There are two wires that come out of the plug for the regulator. The black wire which is the ground wire for the no charging light on the dash when the alternator goes bad, and there's a yellow wire that needs to be plugged in for the alternator and the red wire from the battery. The moment I plug that yellow wire in the alternator makes a whining noise and slows down the alternator. This only happens until the motor is warmed up. If the motor is cold I do not hear the noise and with my meter plugged in It's reading the 14 volts that it should be giving out. I tried pulling all the fuses and than restart the motor, but it is still doing it. I jacked up the car and checked to see if maybe one of the wires on the starter melted and shorted out but they all were fine. The ass whole before me changed the evaporator and I think he might of screwed something up in there, but I drove the car from new jersey to long island and the car was just fine. Anyone have the same problem with this car and figured out what was up? also when the keys in the ignition the stop engine temperature light comes on which it shouldn't and is telling me the problem lies behind dash but I am not sure. Any help would be greatly appreciated.

Get a wiring diagram and track the wires and circuits in the charging circuit. Could be some problem in the harness, no quick answer for this. Why did you have 3 alternators?

I am trying to find a good wiring diagram I picked up the Chilton book but it doesn't give me a diagram of the wires leading into the dash and it only shows one wire going into the starter but there is three. Alldata only goes back to 82. Do you know of anyplace online where I can find one? And I went through three alternators because the first one from pepboys looked like it was already opened and returned the second one I bought at advanced auto burnt out in 15 minutes because I kept putting the wire back in after taking all the fuses out to see if that corrected the problem than that alternator took a shit and now I put on alternator number three trying to determine what would be the next course of action.

Try googling the wiring diagram, seems to be some.