Since Google has not yet announced availability of their prescription lenses and frames, perhaps the Glass Guides are not allowed to talk about them yet? They're not going to advertise Rochester Optical's frames and lenses, as RO is not affiliated with them.
You can remove the Glass body from the frame and attach it to your glasses, if you like. Some people use zip ties; I used velcro strips. This may help with the discomfort. Depending on your frames, though, it may place the Glass screen in a less optimal place, though. I ultimately went back to using the factory titanium band and bend the nose pieces so that they would sit on the bottom lip of my frames, moving the Glass into a good position and making it so that only my glasses are touching my face, alleviating the discomfort.