Can I get a little help here please. I have a customer that has requested we build a bed using a single course of 6" x 8" blocks butted together no cement. What is the proper method for prepping the ground. The soil is primarily clay under the thin layer of topsoil the builder put down. My plans would be to lay out the shape of the bed, remove existing turf exposing the clay. Do you guys suggest putting down any type of aggregate or sand prior to placing the blocks?I would thing having a layer of sand would help level the blocks as we go. Any help or advice would be apprecaited. Thank you in advance for your time.