Are you using an air compressor / spray gun or cans ?

Used 4" roller for base and top coats and  art to be applied by "stippleing" ( small brush. using only the very end and tapped up and down) will get some pics of this method. it leaves a nice smooth finish and no brush strokes. A signwriter friend will be doing the "pins and balls" by hand and the stripes will be masked off and "stippled"