I second turning it into a white spot with an opaque applicant of some sort. I never like doing anything to negatives, but I tried the etching-print-then-spot method, but the spotting then spreads like crazy and is worse. I know as a print it looks worse, but you're not going to find a better method. You can use a high concentrate bleach, but it will be the same size as the negative retouching opaque technique, but at least you only have to do it once and not every time you print.