I have traced a bad shimmy to the electric fan motor. It would appear that the motor is vibrating rather severely. The choice I am facing is to either replace the fan motor for about $150 or should I just go with an after market fan and if so, which one?
Pull the connector. There are three pins. One is ground and the other two are the high and low fan leads. Run jumpers from the battery to two pins on the fan harness. If the fan doesn't come on move one lead to another pin. If the fan still doesn't come on the motor is toast. If the motor is working you will be able to hear and feel the difference in fan speeds for the high and low.
I've had great success in replacing only the motor in the past. Getting the fan off the shaft is a huge PITA! But it can be done, just gotta be patient. The fan motor I bought was about 60 bucks.