Home Made Rotating Arm:

1.  All this consist of is two brackets with a screw and nut in the middle.  Attach one end to the fan motor shaft (this is the shaft that is hooked to the arm that turns the fan from right to left, not the shaft that turns the fan blades) and the other end to the coat hanger that is connected to the dimmer knobs.

2.  Coat hanger is bent so that one end fits into the dimmer knobs and one end fits into the rotating arm.

3.  Dimmer switches connected together so when one turns on, the other turns off.  Glue the dimmer knobs together and drill a hole in one for the coat hanger.  The coat hanger will turn the dimmer knobs making on turn on and the other turn off.  The coat hanger will not make the knobs cycle, the knobs wil only move back and forth so that the dimmer shafts will not interfere with the operation.
 

Please Note that I do not endorse this method of wiring for the dimmer switches.  There are numerous ways that the fading of the lights can be done including the purchase of a fader switch from   Tom Walker at Scream in the Dark  for about $75.  We constructed our own fader controls using a 7 rpm gearmotor (~$7), two light switches with gang boxes and a little imagination.