Abstract: A tillage implement which has both deep tillage subsoil shanks at the rear of the machine and relatively shallow running, residue cutting and topsoil mixing discs at the front of the machine provides for expeditious depth adjustment of the discs through spacer blocks that may be inserted between the underside of the frame of the implement and the tops of the gang beams. The blocks are designed to be clamped in position beside pivot bolts and angle retaining bolts of the gangs such that the blocks may be inserted or removed by merely loosening the bolts instead of completely removing the same and without interfering with the ability of the gangs to be angle adjusted fore-and-aft. The configuration of the blocks is such that they may be stacked one upon the other to provide an increased range of depth adjustment without sacrificing rigidity of construction.