Once you've got it dry try a product called Fertan on the rust. It stops it going further until you can he it sorted properly. I've used it on both my Defenders with excellent results. Get it on fleabay.

Hi all, just got round to registering at last. Need some advice on my landie. I have a defender 110 commercial. It's an ex electricity vehicle which came with hydraulic winch,full length galvanised roofrack and racking in the back. Nice! I am running 285/75 16 general grabber at on 8" steel...