Mine had over 3/4 turn of slop when I got it. As Brian stated, take it all apart. Be very careful taking the front end from under the tractor--the wheels, axle and housings are heavy and top loaded and will flop every which way. I use a hydraulic lift table from Harbor Freight to handle the front end unit while removing and reinstalling--works great.
Brian mentioned the pitman arm/sector woodruff key--that key way and key were very wallowed-out/worn on my SA. I obtained a larger key and custom filed the new key to fit the worn ways in both pieces--takes a while but performs just a good as a new unit since the shaft is tapered and can be tightened with the nut.
Barn_cub