Further to David's comments re corrosion, I continue to be amazed at what spontaneously decided to rust on these cars. Having an hour or two today I tackled some under bonnet tidying I've been meaning to get around to: the ABS pump carrier and the horn brackets: the surface rust offended mine eye...... Now nice satin black.
Unlike MGR, I applied some primer before the top coat....
I removed the black plastic centre cover to give a little more movement on the brake pipes.... Bugger me, the wiper motor casing was also rusty. Dealt with that too.
I'm inclined to think that, to save cash, they diluted the paint with canal water rather than thinners....