Good points Jim, regarding direction and type. I used to fix all of my own audio gear and electronics. Had a collection of Sam's manuals. Now everything is mostly proprietary modular IC's .
Cheaper to buy new than repair even if you could get the parts. I Still love fixing stuff.
My crawling around under cars, at least on my daily driver are over, too many years digging blue stone out of my back from crawling around under the car in rain or slush. I don't even do my own oil changes anymore. My 70 TVR is the exception but it is a toy.