F250racer I just removed mine today this what I have 1959 F250 4x4. As stated earlier the slot on the zerk end is just for twisting the pin enough to line up the keeper bolt, no threads on pin! the lower pin can be removed by using a drift ( I used a long 3/16) through the hole in the frame. however that hole on mine is not lined up exactly with the pin the drift needs to be angled down which may be difficult if your bed is still on. once the lower pin is out you can raise the frame or lower the spring in order to use the drift to remove the pin attaching the shackle to the spring eye. WD40 helps
Good luck! I forgot to mention the perpendicular stud/bolt needs to be driven out also! Remove the nut and drive the headless bolt out. That is what locks the pin in.
Wally

 

Thanks for setting us straight Wally.

Tom