Just to throw in some extra thoughts. The story isn't just about the rib cage, it's the lungs and heart underneath. It isn't a simple matter to dive in and shrink the rib cage. You have 10 ribs directly encompassing the heart and lungs and two lower ribs that provide support to some muscles. Taking out the lower ribs would affect the lungs, the diaphragm and heart as well. I am sure many have issues with breathing afterwards. Infection, pneumothorax, pain and rib regrowth are all very real possibilities. The rib cage is incredibly complex from an anatomy and physiological standpoint.
I too suffer with a large rib cage, but, for me at least, I am working more on the acceptance then the ability to change it. The more research I put into trying to change it, the more frustrated I become and I have learned to either wait for the technology to catch up and/or magic potions/devices to solve all the problems....
However, as was said before the options are corset training, fat redistribution, clothing and some pretty invasive surgical procedures.