I agree Jo with not adressing blood flow issue's although I think they had the swiss ball stretch you have mention here and other threads. I will have to try that one to see if it helps me.

My chiropractor suggested which has some good stretches although the ones where I have to raise my arms are a problem due to blood flow stopping are a problem and they are the ones I avoid

I haven't posted enough to put the link here but will send the link to Jo-
added- http://www.nismat.org/ptcor/thoracic_outlet/index.html