OK, so I didn’t do this myself but we did have to get up very early this week and drive the Defender to Rustmaster to have them do all day spraying of various parts of it with Dinitrol products (the black, waxy finish in the images). This should hopefully rust proof the chassis (inside and out) and other parts of the underbody for a good while. I will say that doing this looks to be a very messy process, judging by the state of the guys and their garage!