Steering gear box adjustment

Steering gear box was adjusted that is in VW 1302 Super Beetle with worm gear mechanical construction but without the ball recirculating system like some recent design as to reduce backlash to the minimum value. Too much tightening screw in would cause frictional resistance, so very precise adjustment is required, remembering that a little free play should be remained to keep lubricating membrane remain adequately preventing irreversible wear on the gear touching surfaces. After adjusting the gear box, a little backlash noise was still discerned on the opposite side, yes, the criminal is drag link construction. I'm think over about this innate defect here, too much clearance between main shaft and supporting brass bearing is the reason. Though some thin plastic film insertion, probably 150-200 micrometer thickness, might be effective to eliminate the backlash, application some ball bearings on top and bottom of the case would be the measure for this problem by machining the case to accept them. Displacement of the driving direction while straight running would be far improved after these counter measure methods. Worm gear steering gear box constructing is not always inferior to rack & pinion steering gear box, because the kick back shock from the ground surfaces is consumed better than latter one and some distinctively comfortable steering reaction is obtained, former one is meaningful, not so bad.