I wish I could help, but I am on the other end of the scale and retired. An improver refers to an apprentice in the last two years, i.e. years 6 and 7 of their apprenticeship, where they spend 6 months in 4 different firms so they get anything not taught where they did their apprenticeship. Even in my day that was well gone, with the day release and evening classes replacing it.
We do get volunteers where I work trying to get some work experience, but I would assume you want paying, the minimum wage works against you, when I started apprentices were paid very little, but at least paid, my wife had to pay to be taken on with a hair dresser. But today employers can't pay what they think the person or job is worth, so the night watchman is a thing of the past, either nothing or minimum wage nothing between.
As to the levels, even BS 7671 is level 3, as is an 'A' level, there are some level 2 courses, which is what a CSE, 'O' level, is. So the C&G 2391 is quite a hard level 3, and C&G 2382 or what ever it is called now, shows you can read a book. Even in my day the technicians course was far harder than a plain electrician.
Age is also an issue, I have to go and watch a girl work, she does work hard, and I don't mind, but she is under age, and also no one should work alone, but age also changes what minimum wage is.
Full marks for trying, but really it needs you to personally call on people, and also state what sort of work you want, even within the electrical trade, petrol-chemical, shop fitting, manufacturing and domestic are very different. Can't see a house basher being asked to work on a PLC or three phase, although it is moving that way.
I did out of interest look at your profile, but
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does not really help. You profile is a type of CV (Curriculum Vitae) and it really does need to show you in a good light.
I know when I went to University they were suppose to find a placement for me, not that at 60+ they did, but it is worth seeing if lecturers can help you.