Hi Will, I wish you success with the hunt for an apprenticeship but if not there will always be someone willing to give you a start at the bottom end of the market (light aircraft, components etc) and teach you on the job. OK you may get taken advantage of and the money will probably be crap to start with but you will be learning and once you prove yourself you can work your way in and upward even without aviation qualifications initially. Some of the best fitters I know had no formal aircraft teaching but were like you with a mechanical background. The UK are desperate for Aircraft fitters. I work with a large airline and we are taking on the experienced light aircraft/ forces guys and honing their skills as there are so few trained people about now. those people need to be replaced so that could give you a chance.