Not really, there is documentation on UI Scripts here.
https://docs.servicenow.com/bundle/orlando-application-development/page/script/client-scripts/concep...
After that you are going to have to figure it out on your own by looking at the page HTML and using javascript to hack it up. It will probably break at some point because ServiceNow will change something and you will have to recode it. You may also cause parts of the interface to not work properly. I would tell the people that are asking for this that it is not worth the dev time and grief it will cause.
