Downloads: gui.php, gui.backup, gui.zip
Install this plugin and extract the backup file, and then unzip your gui buttons to your farm img folder (usually boltwire/farm/img)(see the plugins installation tutorial). It should create a gui folder with various gui buttons inside, for your edit boxes. To add or remove them from specific forms add/remove gui=true as a parameter to each box. To change the buttons, you can edit code.embed.gui, just do it carefully.
Multiple Button Sets
It's also possible to use multiple gui button sets by assigning the gui parameter a page name, rather than true. This could allow you simple and advanced button sets, or even different graphics, on different forms.
To do it, create a new embedded page to contain the links to the new button set. It is easiest to copy one or more lines from the page, code.embed.gui to a page named: code.embed.gui.alternate_name and then modify those to suit your needs. Add or switch the form box parameter from gui=true to gui=alternate_name (based on the name of the gui page).
Note: Just released an upgrade to make it work with 2.65 and above. Please upgrade BoltWire before downloading this newer script.