Your on board wrench is obviously longer than either SWIMBOS or mine and having watched someone attempting this in a car park some years ago I was horrified to see the unattended wrench fly off the bolt and assault the nearest car as soon as they tried to move it!
I reckon 50% of folks on the road wouldn't have a clue which way to point the wrench to undo the nut and even fewer would know how to use the jack or where to put it
Still, all good fun as long as it isn't me!
As for the spare in the boot, when Sheila bought her car I moved her tools and stuff into the wheel well and made sure she knew how to get at stuff, even in dim light, cos I'm like that. When I tried to get the jack out of the hidey hole it was secured in, there was no way on God's little green earth that I could remove it.
We took it back to the main dealer and asked the nice salesman who had sold it to her if he could help. 'Certainly madam!' and off he went to show us how. Ten minutes later and having dragged the service manager out to demonstrate how it should be done, (and he having failed, despite resorting to the owner's manual) one of the techs came out with a bloody great screwdriver, popped it out after a bit of a grunt, then pulled a Stanley knife from his pocket and cut off a sliver of plastic from the offending cassette!
Simples!