Ah, as ViperOne for the M7 is based on the International GSM release it didn't occur to me that it might include any ATT apps. I've seen some options in the installer for ATT-style icons, but that's all I noticed. But of course I'd have chosen a default Viper install and then tailored that, so could well have just not looked at anything that seemed carrier-specific.
Yes, go through the installation again and just deselect anything you don't want during the install (one of the questions you are asked during installation is whether you want to uninstall any apps/choose which apps you want to install).
If you are S-Off you can just mount system read/write then use Titanium Backup to uninstall the apps, but I'm guessing you are not S-Off.