The original pieces are moved to the side. The pins mark their original location. I level the ground and lay down 3 inches of gravel in a shallow depression about 2 feet in diameter. The gravel is tamped down with a rubber mallet. The headstone base is placed in it's original position and using a combination of tamping and moving gravel, is made level and plumb. It feels really solid and I know the gravel will allow melting snow and rain to drain away from the stone and reduce the likelihood of frost heaving the soil.