Auto body repair & detailing: Removal of windshield wax, rain x, soapy water

Question
I applied Rain-x windshield wax on the outside of my 2000Toyota camry about 5 months ago and would like to remove it from a small portion of the windshield without causing damage.  The Rain-x technical support recommended Soft Scrub but that did not seem to work. The decals for the military base registration will not stay on for very long. I even tried using glue but that also failed.  

Answer
That's a new one on me!! I would suggest; washing with hot soapy water, then lay a wet towel with hot soapy water on it over the area for your DOD decal, then scrubb it with hot soapy water again. You will need the hot soapy water to sit on it as long as possible (this allows the silicone to break down).
I hope this helps,
Shawn