As I have used the original yum-pull script, I discovered that one very slow aspect of its operation was the removal of old files once new rpms had been downloaded. I modified the checkmirror script slightly to tailor it specifically for this purpose and called it managemirror. You will need this script in addition to the yum-pull script provided here. It is a low version number but comes from a much improved checkmirror base so I don't expect it to have a very long time before moving to a full release version.
You can access the script via this managemirror link using the password managemirror.