Yep... compared to the cost of labor, a few hundred extra for a true 6 inches of 4000 psi concrete is well worth it. Tractors and a backhoe will be driven on it (not on the 4-post lift, just the floor!)

Phase One complete! Now it has to cure for a while so we can start on the six foot strip to the right. Since my friend doing the prep wants to do as much as possible with his 'hoe, waiting a while is prudent. Either that, or we have to hand-dig the dirt in sticky southern Missouri heat...