It's real simple! On top of the stearing box, there is a slotted screw with a nut on the outside. Hold the screw with a large screwdriver and loosen the locknut, then have someone turn the stearing wheel back and forth while you tighten the set screw in. When you get rid of the slack, tighten the locknut. Then check to see how tight it get's on a full turn. The reason for that is because the two lobes that ride in the worm gear to turn the pitman arm tend to wear a little in the centre or straight ahead position. When you adjust the set screw it might be a little to tight once you get the wheel past the normal straight ahead range. You might then have to back of the set screw a bit so it won't be too tight on the whole turn. I hope that helps you out.