They can be really tight in the axle it's self, greasing the king pin to spindle bushings won't do anything for the axle to king pin fit...
Give it a try with moderate blows with the big hammer and sturdy punch, while supported solidly underneath, on an anvil or concrete floor.
If that does not work, then to avoid possible damage by continuing down that path, it would be best to take it somewhere with a hydraulic press.
Grigg
