After temporarily removing the upper torsion bar from my Mk2 (better access to the head), I've found light rust:

What should I do to protect the turret before I screw the torsion bar back on again - Is there some sort of grease I should apply e.g. copper grease? The bolts for the torsion beam do not have nuts, they are just screwed straight into the body shell, so should I also be protecting the bolt holes as well?
Cheers for any suggestions.