Regardless of microstructure of metal, heat up the thing you want to expand and don't heat up the other thing. Don't need red hot to get a .001. The penetrating oil, as said, will do it's work. Use an air chisel with a very blunt tip to vibrate the parts. Vibration is a good tool. It is the baby brother to BFH. This will greatly increase penetration of the oil. Do it a lot around the whole area and do it on the pin. You can bang bang in between sessions if you have aggression problems. Make sure you can notice the slightest movement so you will know it's working. That will give you renewed vigor.
You can also buy a Snap-On king pin remover for about $8000.

You heat things red hot and bang hard on them, they may bend. Try to support things around there with a jack and piece of wood...or chain them to the frame.

Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn