I understand what your trying to do here, let me tell you how i managed to get mine right for the mirrors and the wing.. I went to Autozone and tried to find the correct white i needed to do it and until i found out the match up paints wont shine without going over them with clear coat (vehicles now use base/clear) I picked up a can of Nissan white, i, of course didn't buy the clear coat but took it home and tried it on a piece of plastic and it matched up perfect.. I don't know if you get the same results with the black but its a shot.. being the stripes (mine) are the same color as that Nissan paint i bought whats the chances that black could do the same for you? I know it sounds nuts and maybe i just lucked out but for 8 bucks to try it it cant hurt. Ive tried to find something that may help you with this, the way i did it sounds crazy but it came out just the way i wanted it, i couldn't find anything so i thought id just tell you how i did it and you can call me nuts or give it a try.