Chris,(posted 9682 days ago)The scaling formula, (player.score / highest.score) * (100 - PP) slightly modified would do it. Again taking my simple idea of using place information, I would suggest this:
(player.score / highest.score) * (100 - PP * finishing place). e.g. If PP=10%, then a 3rd place score would use 70% of the original score. Again, you're limited to only the top 9 scores, but I don't think this is really an issue. It sure beats only the top 3 counting!