If the Pitman arm is slotted, with a pinch bolt tightening it over the sector shaft, the bolt needs to be removed completely, not just loosened. There's a groove in the sector shaft that will keep the Pitman arm from coming off if the bolt isn't taken all the way out. Once the bolt is removed, use a 2-jaw puller to persuade the Pitman arm to move if necessary. Sometimes a few medium-firm taps with a BFH will get the job done! On the steering gears with one large nut on the end of the sector shaft, a very heavy duty Pitman arm puller is definitely required.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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