UITabBarController without a Storyboard

My Xamarin IOS project uses a Storyboard. Its a tabbarcontroller app, I'd like to modify the number of tabs in my root UITabBarController.

You can't add or remove tabs if you crate the tabbarcontroller from a Storyboard. I'd like to replace the root view controller with one that is not created from the Storyboard. I'd still like the Storyboard for some of my other classes.

Instructions for creating an empty Xamarin project or removing the Storyboard from an Xamarin project using Visual Studio on the Mac do not work.

I think the new SceneDelegate removes the ability to set a root view controller in AppDelegate.

Thanks,
Gerry