Can anyone tell me the diameter of the hole in the pitman arm (the arm that is connected to the steering gear box) where the ball that connects to the drag link is pressed into. This is for a 1949 chevy 3100. Mine is 5/8" but Jim Carter truck parts sent me two drag link replacement balls that have 3/4" shoulders where they press into the arms.

Is my arm wrong or is their part wrong. I see classic parts sells one with a 5/8" diameter shoulder