You can try thinning the 'oleum with some Clear enamel, or spar varnish. I saw a VW that a friend of mine painted with a brush! The varnish slowed the dry time and let it smooth out!.
Anyway, If you are going to spray this stuff, I hane no exoerience with the 'oleum. Spend the bucks to get some real paint and a GOOD reducer.
Althought the paint will cost some bucks, think about all the time you will put into prepping the body!. Remember the paint will need to be cut 40% to 50% with reducer, depending on the weather...
Oh and yes, the Auto paints have decent UV inhibitors that keep the color stable.
Shop around, paint cost varies, Acme is good paint and it doesn't cost that much. House of Kolor is, of course at the top. Also check different colors that may vary the price too.
If you aren't picky about the color.. (Humor me here) Check with the paint shops to see if they screwed up an order and botched a mix job... They will sell you the paint cheap!

Toaster..


"I love the smell of Urethane in the morning..."