Why not use some of the leveler blocks, or wood, to run the wheels up on before the area that scrapes gets to the high point. I'm assuming that the wheels will clear the leveler/wood and be parked on cement, but even if they stay on the wood, not levelers, and are evenly distributed is okay. Unless the levelers are the flat, almost solid ones, I would not park my tires on them. Those hexagonal leveler blocks are not good for parking vehicles on. They do not evenly distribute the weight along the tire.
Here is a link to a PDF file on Michelin RV Tire Care. I figure that if it is good enough for Michelin, it should be good enough for all other tires.
http://www.michelinrvtires.com/asset...e_June2009.pdf