I've been wanting to do this for a while and have been researching the options. The following thread has some good info:
Monster electric cooling fan upgrade. long. w/photos. | Moparts Question and Answer | Moparts Forums

And there has been a controller made for this fan: http://ma-uav.com/FanControllerv3.html.
The discussion about the controller: http://board.moparts.org/ubbthreads/ubbthreads.php/topics/1128594/1.html

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1986 300E (3/2002) Rear ended and totaled (10/2009)
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