An agricultural tillage implement including a carriage frame assembly and pull hitch towed by a tractor and forward and aft secondary frames supported by the carriage frame assembly. The forward and aft secondary frames mount gangs of disk blades for tilling the soil. The secondary frames establish a plane and the aft secondary frame is connected to the carriage frame assembly at a greater distance from the plane than the forward secondary frame so that the depth of penetration of the disk blades is uniform during field operation. The tillage implement has outboard wing sections pivotally connected to the secondary frames and annular shims are provided to establish the wing sections and secondary frames in common plane during field operation, the annular shim being rotatable about central axis to present a common surface to the implements irrespective of the orientation of the shims.
