My son-in-law is a mechanic so he will replace it for me. I managed to get down on the ground and remove the backbox. It had rusted through close to the clamp so unfortunately the tin can idea wouldn't work.
It is quite rare to see the DIY mechanic repairing his car at home, As a DIY mechanic I perform all my repairs and servicing on my cars, motorbikes and bicycles.
Neighbours marvel when they see me working on my car, just a simple service, change engine oil and filter, they query "who taught you to do that" as if it requires a BSc to drain sump oil , well it is not rocket science to drain oil, change a filter and refill with fresh oil. I also explain the cost and time advantage, I can change the oil in less time than I take for the double round trip to the service point, and, it takes several hours of paid employment (disposable income) to pay the bill at the service point. It is a concern that for many the simple mechanical skills requiring handtools and common sense have been lost?
I blame the modern education system, classes such as woodwork and metalwork are considered obsolete, yet gave boys the opportunity to acquire confidence in mechanical skills, dads would show sons how to use tools.
A local Science Academy has a Primary Technology Workshop, I thought of a metalwork shop with Lathes and milling machines, Quite Wrong, Primary Technology in a Science Academy is apparently a Pottery class, and in the Academy Taps are not BA or Metric , only heel or toe on a wooden floor.