I would almost want to have a digitally printed heat transfer made since the colors will need to be vivid to satisfy the customer and the 4 color process might make that a little chunky ... and that is more than 6 spot colors (black, brown, orange, red, yellow, light blue, royal blue, teal ... and navy??) so even with a color seperation you're going to get some funny colors that might not be exact (especially the red)