[MarkECampr]

I stumbled into the method that "therink" describes.
A site I had, had quite a slope to it, so I let the chock take the weight of the trailer. Now I set the front or the rear chock, let the truck press against it while the DW sets the opposite side of the wheel.
Haven't had too much luck with the tire spreader type of chock. I find that the most front-to-back flex is where the rubber hits the road.
A set of scissor jacks midship, improves the side to side movement. Always check the scissors jacks on the second day - the ground will compress.