Get some freakin' Methyl-Ethyl Ketone (Before you ask, hardware store-paint and thinner aisle) and soak the bottles in it... If that don't take it off, you'll need a hammer... Testor's Liquid Cement is mostly MEK and will work in a pinch, but it's way more expensive per ounce than a pint of MEK..
Then get a couple metal paint cups... Unless you got some 15.00 El-Cheapo, Suzy Homemaker, POS Testor's or Badger brush, it'll take a cup... Then you mix in the bottle and pour off into the cup to paint...
Then enroll in a Vo-Tech school and take an autobody repair course... Pay special attention during the blocks of instruction on painting...
Or- and this is what I think you'll do anyway- continue to do things the hard way and complain that "no one gets you", and make another smart-azzed post...
This airbrush maintenence stuff ain't hard, man...