maybe it's just me, but i would have made those ramps out of steel, welded together, with rubber gripper strips bolted to the bottom.
definitely chock the rear wheels, and if that would be a semi-permanent parking spot, i would think seriously about sinking some anchoring points in the driveway [front and rear] to chain the truck fast so it couldn't possibly move in either direction while up in the air.
of course that's just me thinking.
your mileage will vary.