Oh God, I knew there was another fluid question... what brake fluid? And does it matter if I 'mix' brake fluids? As I don't want to drain what ever is in there when topping up... same with antifreeze, can I just top up what is already there?
The best antifreeze for a Minor is the genuine bluecol traditional a/f. It may require flushing every few years, but the modern long life preparations aren't really suited to our engines and hoses. I was sceptical of this until I tried a modern variety and found that I was losing water. Pressure testing the system (both hot and cold) could find no leak. Swapping radiator caps with another car, and anew cap, made no difference. No trace of a leaf, just water vanishing. Change back to Bluecol, and the car has been fine ever since.