Rust spots
 

Can anyone recommend a decent rust neutraliser, looking at using something like the hammerite kurust pencil unless you nice chaps can think of something better.

These make amazing rust killers
http://www.bilthamber.com/
And this is a brilliant primer.
http://www.autopaint-pro.co.uk/1l-bo...imer-121-p.asp
Both of these are used in the classic car restoration world and are miles better than off the shelf type stuff available from Halfords and the like

I bought some dynax S-50 anti corrosion wax the other week (first link in Fred's post) to treat a few bits. Brilliant stuff!

The Bilt Hamber stuff is excellent.

I have just used the Bilt Hamber hydrate80 on a few rusty spots on my inner arches
will report back in a few years as to how good it is but it gets very positive reports

I've never had a problem with Hydrate 80 but I know couple of folks that have had the rust return.
From my experience all Bilt Humber rust treatments are about the best available.
I exclusively use Bonda Rust Primer below any top coat as it's amazing stuff.