Hi Duke
Here is his answer:
He needs to add more coats of paint. It sounds like it's a transparent black. There are actually 3 different black tints in the cormax line. Putting the topcoat over a tinted primer isn't a good idea, because that means that if there is a spot with more or less paint it will be MORE visible. The best route is to have a spray out card with one coat, and then cover up a strip with tape and do a second, another another ect... until he achieves full color saturation. That way he will be able to know how many coats he needs to do to achieve full color saturation.
Dakazman