Separate manifold blocks are connected to the ends of tubular piston rod end portions of linear hydraulic motors that are parts of a drive assembly for a reciprocating slat conveyor. The manifold blocks are removably connected together by bolts and when connected complete passageways in the manifold block assembly that connect the linear hydraulic motors with each other and with pressure and return conduits. The end portions of the linear hydraulic motors are connected to transverse mounting frame members by spaced apart clamp assemblies. The clamp connections stiffen the end portions of the linear hydraulic motors and minimize deflection at the centers of the linear hydraulic motors.