The Harrier doesn't use the same standard symbol files that Eagle Dynamics uses, therefore some items on the RWR are slightly different. These are the codes I've noticed/collected over the last year using the Harrier.

Also thanks to Chucks guide I've added some reminder graphics to the top of the Kneeboard.

To install, unzip the png file to C:\Users\<YOUR USER>\Saved Games\DCS.openbeta\KNEEBOARD\AV8BNA