Sorry for not taking any pictures. At the bottom, and Inside of the push rod there is a very flimsy bearing assembly, this bearing is of a sandwich type, holding ball bearings inbetween two plates. The bearing is located close to the electronic box that contains the motor gears. As the motor spins, the 24" screw turns, extending or retracting the push rod. As mentioned earlier, the outer bearing assembly is tacked welded to the inside of the push rod, the 24" screw goes thru the middle of the bearing and is held by a nut, this nut seems to tacked welded to the tip end of the screw, the other half of the nut, a piece of a blade is also tacked welded, this blade goes into the motor assembly, the motor spins clockwise or counter clockwise, making the shaft extend or retract, via the plastic nut at the opposite end of the push rod, which this nut seems to be pressed fitted into the end of the push rod.
It is said that a picture is worth a thousand words, sorry again for not having taken any. I just hope that this explanation is somewhat clear of what I did.