Reallocating bootcamp partitioning

As I understand how the system has to fudge it to simulate a MBR Windows-friendly environment on top of OS X's GUID reality, the thing gets cast in stone. Safest bet is uninstalling BootCamp so all gets returned back to a single OS X partition, then redoing the install/setup from scratch with the new sizes.

Note that once you have it set up and working, the disk partitioning becomes untouchable. No resizing or adding additional partitions whatsoever. BootCamp supports only two partitions: one for OS X and one for Windows, in the order set up and in the size allocated. Any fiddling with that will screw up the Windows side, the OS X side or both, with probable data loss. If there ever is no longer the need for the dual system, getting rid of the Windows side of things is only thru the BootCamp utility in order to recover the disk space and return it to OS X.

When Windows gets installed, be sure to install all the drivers BootCamp provides for that OS so it will recognize and properly use all the Mac's hardware. Particularly critical if the MBP has a Retina display.

Have fun!