Jeff,
When all else fails use your trusty lacquer thinner.
Actually you have to be careful as lacquer will make arcylics gum up in the airbrush if not cleaned thoroughly enough.
Did you try that cleaner that you mixed up? If it is an acrylic then that should work.
Mike
“Wisdom is the right use of knowledge. To know is not
to be wise. Many men know a great deal, and are all the greater fools
for it. There is no fool so great a fool as a knowing fool. But to know
how to use knowledge is to have wisdom. " Charles Spurgeon