I am trying to replace my tub spout with a universal tub spout and I cannot get the old one loose, any idea's?

Try using a large monkey wrench, for more leverage. It should simply twist off. It's probably stiff due to the teflon plumbers tape around the threads.

If it had teflon tape on it, you would likely have it off already. More likely it is pipe dope, crud, rust, and corrosion. A bigger wrench can lead to chopping a hole in the wall to repair what you twisted off. Heating it with a torch and quenching should work. If you don't have a torch, try hammering on it. If you can get at the joint, a little penetrating oil may help. I like spray silicone. The hammering will break up the crystals of oxide locking it in place. Spray, hammer, twist, curse, spray...

Are you sure this spout is screwed on and not a slip on with a set screw? Check on the underside for a possible set screw, if it is there back it out and then pull straight out on the spout with a slight twist. If there is no screw then try Labman's heat/cold approach.