Been using my new Edge as my bowhunting vehicle this season. We are getting lots of rain here and the muddy roads are killin me!!! After a few days, the whole body is coated with a nice thick layer of mud. After spraying the heck out of it at the local coin wash there is always that thin layer of dirt that the pressure washer just can't remove. What is the best approach to washing this layer off without scratching the clearcoat? This ride always has a nice coat of Duragloss 105/601.