before thinking it's your steering box, have a friend go down and look at the pitman arm/draglink while you just shimmy the steering wheel in the slop region. That way..if you're moving the wheel, and the pitman arm is not turning...then you know the box is your problem. If it is moving, then it's with your steering linakages.
if it is box, you can adjust the rack gear up and down a little to change backlash and such. But that adjustment is fairly slight, and you would probabaly not feel much slop in the steering wheel even if it isn't adjusted properly.
_nicko_