as far as the black bit goes.... you will not be able to die them another color. It is a transparent dye meaning that what ever color it starts out of will remain. So if what you started with was bright blue, you could only go to green/dark green/dark blue, purple, brown, or black. To get green you could use green or yellow. To get brown you could use orange. To get purple red. Because black is the darkest you can get, there is nothing that will lighten it. The only thing you can do is paint it with a flat/opaque paint such as spray paint and then put a varnish on it.
Its the only way.