Display Different Ads for Different Posts' Word Count

[6piston]

Hi,

I know this may sound confusing, but there is a request by my potential client asking if i can do this:

It Involves:
-a poster replying or creating a thread.
-conditionals: post word count

There are 3 Leaderboard Banners: Z,Y,X

- Fixed leaderboard banner "Z" on Header when thread is viewed
- Banner "Z" is replaced by Banner "X" when poster posts "X" number of word count for his Thread or post upon being redirected back to page
- Banner "Z" is replaced by Banner "Y" when posted posts "Y" number of word count for his Thread of Post upon being redirected back to page

I'd really appreciate it if anyone could tell me how to potentially do this OR is there like an alternative way or similar ways to satisfy my client's needs

Thanks in advanced!
Tom