A life's (fatal) lesson on how NOT to maintain magnetos

My son and I (Both IA holders) own and operate an aircraft maintenance shop here in Arkansas. (KELD) I've been maintaining aircraft for over fifty years, my son has 23 years of experience. We maintain the majority of the planes based at our field and we perform flight line maintenances for the local airlines. We could both write a book about some of the "nightmare stuff," done by owners, we have found on planes that come to us for maintenance and inspections from other airports. I would be proud to say, that all of our regular customers are straight shooters. They leave the maintenance up to us. 14 CFR 43.3 Is clear about who and what a registered owner can do (preventive) to his or her aircraft. The scary pilot / owner is the one who has the "it's my damn plane and I'll do what I want to," attitude. Most owners respect the A&P /IA. In the case of the B-17 crash...those volunteers had to of had in their possession a mechanic's certificate or have worked on the B-17 under the "direct supervision" of a person with a mechanic's certificate (A&P) who was "experienced" in performing the particular maintenance the volunteer is doing under his or her supervision. You are subjected to an enormous amount of liability and responsibility supervising "un-licensed" persons. Even when I or my son perform maintenance or inspections on our own plane...he follows up on me and I return the favor. When operating an aircraft..."you can't pull over and lift the hood."