I highly recommend the book "The Diabetes Solution" by Dr. Bernstein. It's written by a T1D-since-childhood who was a manufacturing engineer and used his engineering skills to "debug" his diabetes despite his doctor's efforts to the contrary. However the medical industry rejected his findings on blood sugar control because of lack of medical credentials so he went and got an MD and suddenly more doctors started listening. He basically got ahold of an early glucose tester and turned it into a CGM by pricking himself dozens of times a day and around meals to collect data.