Put lumber under the blocks and have a more solid surface than loose dirt. When Stonehenge was erected forests covered the Isles.
I saw one theory that they rolled the stones along the long axis. You can jack it up a little at a time, and build up stones until it rolls over on the next side. Repeat until it gets to where you want it. Seems to make sense to me.
I think lumber is too soft for this to work either. The stone would just get pressed into the wood.