Jacking Points
As you rarely use the jacking points on your MGB, you are likely to have difficulty in an emergency in getting the jack into the jacking point sleeve due to it being filled with mud and rust. To overcome this thoroughly clean the sleeve, give the surface a good coating of grease.
Buy from a DIY or Sports shop four walking stick rubber ferrules to seal either end of the jacking point sleeves. Hopefully next time you need to use the jack it will be easily located.