Installing (new) recondition steering arm

[farmerjohn39]

When installing a (new) recondition steering arm on the left side of the front axle, this is the one with the two balls welded on p/n A-3131 from Synders, I noticed that there was a grease fitting where the steering arm slides into the front spindle, this would indicate to me that this arm would be free to move, but when I tighten the nut down so I could get the cotter pin in there wasn't any movement. I couldn't find a procedure for installing the steering arm in Les Andrews Red service manual so; my question is; how tight or what torque should the nut be that is holding the steering arm onto the front spindle, or dose the nut just bottom out on the shoulder of the steering arm shaft, or should the nut be backed off a little to let the cotter pin slide into the next slot on the nut ??????