I'm not sure what your auto technology background is, but I'd recommend starting with one of several community college or adult school classes on basic auto mechanics. Although you might want to jump right into engine rebuilding, I'd recommend a basic foundation to start (IMHO).
Here's an analogy using painting (fine arts, not house). What does it take to be a painter? On one hand, you can start with no basic techniques and create a very nice .... paint-by-the-numbers piece. You don't have to know much, just follow the step-by-step instructions and you've got a "painting". You can also get formal instruction on basic design and technique, then do it. Which method sounds best in the long run for those of us without Rembrandt or Monet surnames? I'm sure there are better analogies, but this is just one off the top of my head.
Regards,
Sherwood Lee
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