Hi Ken,
I must admit I'm not familiar with which mechanism is used on those models.
A lot of people that make 'lifting' rides do use studding/ threaded bar that is rotated by a motor and then a threaded collar,(attached to the lifting arm).. runs up and down the thread...a little like a car jack, if you know what I mean....a bit hard to explain. Maybe it's the same idea you mention
All the best
Greg