How to use when change Permalink structure

I originally set my permalink structure to /%category%/%postname%/.
Now I need to remove the Category element and just have /%postname%/

Luckly I only have a dozen posts to change.

Please explain if this can be done with your plug in.

Thanks Joe

http://ww.wp.xz.cn/extend/plugins/quick-pagepost-redirect-plugin/