That does sound like its fun to get into. But nowadays its almost always cheaper to throw things out then repair them. A shame if you ask me. I like the days where you could do repairs yourself way beter.
Right now the course I am doing is (no idea how this is all called in English haha) Switching electronicly. So I am learing how to start and look for faults in the electronic operating systems for engines and fuse boxes. Its just hard to focus for me right now. I do think that otherwise I would be able to do it.