On the other hand, the see saw has the safety advantage of being able to be balanced so that the wheel lifts with gravity if the air fails. The motor needs to be protected from water, dirt, and dust as it is an open frame design. I also need to be able to align the whole assembly with the car.
I found an exercize machine that I took from the dump. It was made to hold heavy people so the bearings look strong and tight enough to transmit the motors 160 lbs of push to the car. Got out the pipe cutters and here is what we have.