I haven't seen anyone mention this method, but where we camp in the Mojave Deserts (very remote and unimproved) it's common to use a shovel to dig out on the high side. You dig some holes in front of the tires on the high side and put blocks in front of the tires on the low side, and then when you pull forward, you can see the whole rig twist uphill and level out. It's pretty elegant and a lot more stable than taller stacks of blocks.
Then when you leave camp, you scoop that dirt/sand back and refill your holes before you leave.