Breaking the handle drag habit

As someone who is a lifelong handle dragger, I'm committed to breaking this habit during the offseason. The feels of the isolated ulnar drill have shown me the benefits a shallow and full release. My question is, what drills or step by step process would you recommend to break this habit? I have found that I really can't release the club early enough (at this point) but unfortunately when I try to ulnar deviate on full swings, my trail arm/shoulder goes internal and causes me problems. I've seen some old videos from Mike Austin where he advocates the feel of an underhand throw, keeping the trail forearm towards the sky as long as possible. Any help would be appreciated!