Reinstalling Windows 8.1 using GPT file format

Hello all. I currently have my laptop formatted using MBR in Windows 8.1, however, I would like to make use of GPT. I understand that in order to achieve a GPT partition, it will require complete reinstall of the OS, wiping out the contents of the hard drive. This is what I am working with, and what I plan to do - I have two hard drives - one containing the OS with programs installed,...