Hi, not an SSC, but maybe can help. It seems you end up doing a good morning at the bottom, I was terrified by your last rep.
Try keeping your chest out from the start and during the whole rep as well as bringing your grip a little bit closer to get the back set thigher.
Regarding the bar position you can check this video: Where to Put the Bar for the Squat | Nick Delgadillo
Wish this helps!