Should work. "Safe" is subjective, especially with no recovery path. Proceed at your own risk.
I suppose if I somehow get bricked, that I can go ahead and attempt the USB port replacement. At that point I'll have nothing to lose. Oh, but with no recovery already installed, ADB will be useless. Grrr... scratch that. Perhaps I should replace the USB port first just to be sure? I love this tablet for watching video and I'd hate to break it.