One thing that made a noticeable improvement (something I found a couple weeks ago) was soft tissue work in the serratus anterior, expecially where it runs under the pec minor and lat. A couple minutes a side with a lacross ball across the serratus anterior, under the pec and against the lat and I can go from not being able to get my arms straight over head to being able to if not further. They can really get glued down to the serratus. Be careful in there as I think there is a bunch of nerves that runs along this area (correct me if I am wrong) so if you feel bad pain back off and reposition the ball.