More work done.
I had a plastic tray underneath the battery. When the car went into the garage for the work doing the tray was taken out and not put back when the new battery was fitted. This gave me an opportunity to clean it up before putting it back on. I also painted the battery clamp with a coat of etch primer and a topcoat of gloss black. It has smartened it up.
The next part of the car to get painted was the driver's door and the offside sill.