Well, then if you wnat it to actually look good, and are going to paint it black....then you need to get real about getting things perfectly straight. Any little dents sticking up need to be tapped down and filled...and the whole tank block sanded....then primed...add a black tack coat, and block some more....any areas with black paint still on them are areas that need to be addressed, and you do that until it is MINT.
Your call....but if you don't, and you paint it black, it will look like $hit, IMHO.
~Joe