The rockwell kingpin is held in by a tapered draw wedge.You have to remove the top and bottom caps on spindle and remove the wedge by removing the lock nut(should take a 3/4 wrench).You then drive it out with suitable brass drift and hammer.The king pin can then be driven out.You may need a hydraulic king pin remover if king pin is too hard to drive out.After spindle has been removed you will need correct bushing drivers to remove and replace bushings.Upon reassembly the end play must be adjusted using the shims provided in the king pin kit.When you buy a king pin kit make sure you specify that you want a ream less kit.if you dont you will have to have a special bushing reamer to size the bushings.Your local parts suppler should have this option there are several brands of no ream kits out thereThe end play should be shimmed to .001 to.025.Hope this helps please let me know if I can be of further assistance.