I wouldn't really fire him. You would approach him like this:
"So, bill. Great job with that bowl thing. Remember how you came here to 'calm the waters'? Thanks a ton for doing that. I know you really care about Kansas State University and the excellent football program that you built (I can't think you enough for that, BTDub). So, anyway, I was thinking. Remember Mike Leach? The guy that has always kicked the ever-loving-crap out of you? Well, turns out he's available and begging for every open BCS job and no one is interested. Crazy, right? So, I think for the overall long term health of YOUR program, I think we should hire him ASAP. Let's do this now, and you can have a grand retirement party at a basketball game or whatever. Cool? Alright Bill, thanks. I knew you loved KSU more than anything, even though those assholes on goEMAW thought you only cared about your ego and legacy."