Can anyone give me instructions on replacing fan blower switch?

Well...I do not know where you are stuck...but first operation is to remove the plastic molding or bezel covering radio and heater controls....just grab and pull from the edges..at normal temperature, not in the cold...it will come...make sure you pull straight from one side just a little, then from the other side.
After that, I think you will see more what you are up to....