Bigfoot leveling and tire leveling help

Thanks all for the comments. I grabbed an extra set of the Camco leveling lego blocks and was able to see 4 blocks was their suggested limit, as posted by MrWizard. I do have a 2x10 that I cut into several squares for each jack so it feels more stable. I did the "maximum" suggested limit of 4 squares for each front tire and drove onto it. It is a lot better now and the weight is for sure distributed evenly in the front (using multiple blocks), but I still don't feel comfortable letting the front tires dangle in the air. It is a lot better now, but still not perfect. However, it will get the job done until we move (here soon). Again, thanks all for the replies!