I would suggest not hitting the kingpin as stated in the Haynes manuel... I've done that and now the top of the king pin is compressed and the threads are squeezed together making it very hard to get the lock nut back on.. "not to mention it leaves metal flakes everywhere"
this method is just to set the bearing up for vibration which I dont see why thats needed thighten up all the way and back it off so it spins as normal works for me