My point is that over swinging does not necessarily cause a flip, actually probably one of the least reasons for a flip. Case in point would be Jamie Sadlowski, Bubba, countless others who do what you describe
Relax left elbow in set up. (Pic 1) Get some better upper torso extension (video Mike and Eric showed ) in backswing (Pic 2). Practice a bit of Snead squat keeping femurs external in initial downswing move (Pic 3), pressure going to right side,not a slide (Pic 4) Get weight (pressure ) over to right heel with right hip rotation, will if you don't slide as much on downswing
I like it...remember to make a change in a motor pattern takes a long time, (especially at our age) your pattern is pretty much set, subtle changes is all we can expect. Also body type plays a big role. To me with the pattern you have a high baby fade would seem to fit. You may want to practice hitting low stingers just to add that shot to your bag and it would help with a bit lowering your ball flight. looking forward to seeing you in person soon....
Mirror work is excellent, remember feel is not real. Watch yourself doing the new moves, positions etc, then correcting them is what you are trying to do. Engage as many of your senses as possible, feel and sight, balance, pressures. Be engaged fully in your practice is the key. Do it, Observe it, Correct it DOC