Prev and Next link – hook

Hi all. I’m writing a plugin that will let a poster pick a category for a post and anyone who is not of a certain level will not be able to see the link.

My last hangup (I think) is that the hidden post title still shows up in the previous_post and next_post links. I know these functions have the excluded_categories parameters, but I’m trying to make my plugin so that you don’t have to modify a template to get it to work.

Are there any hooks or filters that can be used on the SQL that goes and gets the previous and next links? Something like post_where for these functions?

I can post my plugin now (which is probably a little early) if anybody is interested. Thanks.