Hi guys I wanted a 197 tower for my future attic layout I'm in the gathering stage again.. this time I found a Great 197 orange top with out a motor so I have used in the past on the bay these 12dc 14RPM motors heres how I did it
If you have a motor take it out (if you want to)then insert the new dc motor inside easy job I use 100 s clear RTV silicone adhesive then center let dry over night then I use a radio shack inline rectifier diode type motor cover will go right on modification you will have to take out the pin under the silver antenna use a soldering tip to lightly heat then pull out shorten to taste less than 1/4 inch or so use a file till height is achived Either start a tap or drill bit and screw in the metric screw that will fit in the motor. cut of head of screw before or after if after use ice on plastic so it will not get too hot
Thread in to motor AND DONE ! enjoy a VERY quiet 197 Radar Antenna TOWER! 
very smooth and quiet motor .. Best part is I could remove the motor I put in and put in original one .because of the glue I used , (in case the prices go sky high again )..Daniel