Removing Part of a Site

I did some development work eh 2 years ago for a department at my university. At that time, I had developer permissions for a few other groups/departments, so it wasn’t an issue of adding development permissions to my account. The chair gave me the current site at that time as a zip file. For ease, I put it on my domain, I did my magic, and gave him a zip file back. After a few months, the site hosted on the university’s servers, hit #1. My domain’s results was in the top 5, which I didn’t care about really. Sometime recently, they did a redesign, and now doing a search, my site is #1 and the university’s version is #3. Looking at the site, and code I am nearly 100% why this is.

The chair is quite mad at these results, and ordered me to delete his content from my domain. I want the version to live on my server still for archiving, but have it get bumped down. What is the best way to do this without killing my own [overall] SEO/page ranking? I was thinking of giving a 301 redirect on that directory, but would like to be able to show people if requested. I was also thinking adding a session variable to the pages, asks people login to view it. Which I don’t know if that would do anything. It is php based.

What about heading those pages / that section with no-follow?

put a no follow on certain pages you think are being ranked high

thanks, that would work