Default Odd way to unlock bell xperia z or t-mobile xperia z bootloader?

Hey guys,
I own both the bell version of the xperia z, and the T-Mobile version. I ONLY want to use them as glorified tablets. Basically like the Ipod touch version of the iPhone, I want to use them unactivated. For me, its all about customibility and I really want to unlock the bootloader. I know neither of these can be unlocked, but in theory, if i wrote the software of the global unlockable versions (c6602/c6603) which DO allow for unlocked bootloader, would I be able to do it? I know signal would be screwy with the radios, but i dont care since thats irrelevant to me. Any help would be great, thanks guys.