how do you keep that from sliding though? seems like if you were to push the car from the left or the right if wouldn't be very stable on that though. or is there something that i'm missing?
The weight of the car will keep it in place. Think of the car as being on a twin post lift. The best place to lift it is on the frame rails. Push on the car. It's not sliding off the lift. In this case, you're placing the car on something with wheels. When you push it the casters will roll unless you have a lot of resistance against the casters, like the brakes being set or some obstruction. But the weight of the car, being set on four small fixed points will keep the car in place.
