Tinting white area of transfer for white areas on black?

I am doing a short run of black koozies for a friend for just the cost of supplies. There is an image of a white, shaded, car. When printed on Coastal Opaque Inkjet paper the image comes out very dull. I figured it would on black but was just wondering if anyone has tried adding a very light color to the white areas before printing to counteract the bleed through? If so, do you think a very pale blue may help?

Thanks in advance for your experience!

Jessica