The guy I take my truck to has been doing service work for my dad's business for the last 15 years (both commercial and personal fleets), and he is a straight up mechanic. Fixes what you ask him to and unless he sees something that will bring your truck back to his shoppe on a flatbed, he lets it be, but lets you know. Very few of him left as far as I'm concerned.
I'll never let anyone else do electrical work though, cause lord knows, they'll use the same color wire for everything and troubleshooting will be a b*tch.
No one in my family is a mechanic nor has an automotive hobby. We hunt, fish, shoot guns, and drink beer. So I'm pretty much on my own when it comes to doing anything to my truck.
I feel like we should be PMing this cause this poor guy is done with his truck and we are explaining our life stories to each other.