Classic/Antique Car Repair: 1961 Econoline kingpins, econoline van, stub end

Question
I have a friend who is not computer literate but needs some information on changing kingpin bushings on a '61 Econoline van or pickup. He says that only the lower bushing on one side is loose. Can he change just that bushing or does he need to change both on that side? Do the kingpins just press out or is there a lockring as in a U-joint? Can they be hammered out or do they need to be pressed with a hydraulic press. I changed kingpins on something once but it was nearly 40 yrs ago and I don't remember it at all. Appreciate your help.

Answer
There should be a lock bolt through the axle stub end that locks the king pin in place. It is a tapered bolt with a nut on one end. Remove the bolt and drive the king pin out. It should drive out but I have seen then so rusted in place that the axle had to be removed and the pins pressed out.Both bushings should be replaced and reamed as they need to be aligned to center the king pin. This is done with a long ream that will ream both bushing in alignment.
Brad