Re: Oh No - Rust!!
hammerite "Kurust" is a white liquid in touch up or pot form, that stops rust dead in its tracks, turning it to blue-black hard steel. Its very very good and should be used until you get the area repaired.
Just brush or dab it on, leave for 15 mins and re-apply, leave again for 15 mins then wash the area to remove any residue (purple by now) which might stain the paintwork.
Prying the rubber slightly while applying the kurust will get some down behind the rubber so stopping unseen rust too. Then later you can see if an independent bodyshop can take out the screen and repair the chip properly.
Me & Her...
I love my tractor so much, If it wasn't an abomination o' god's law, I'd make it my wife...