I'm running a red premix I get from my KW dealer. The service manager mentioned this to me, but when he found out I was already running his red premix he said that's the best he has. I'm not sure the % mix of it tho.
Getting ready to wash it all out. I know there are a few bugs in there, and dust too. Also ordered the seals for the sides of the radiator to help keep air from going around it. I guess there is one on top too, I'm not sure what it looks like but am going to put all that stuff on and see what happens.