Changing careers at 17 years into a job, is it realistic? - what worked for you?

After 17 years as an electrician's helper I am thinking about moving into a different field. I worked as an electrician's helper before this. I have a little time and a small budget for training. Has anyone made a similar move?

You likely have more transferable skills than you think. Write down what you did, not what the job title said.